MACS Service Reports is the offi cial technical publication of the Mobile Air Conditioning Society Worldwide, Inc., P.O. Box 88, Lansdale, PA 19446. The material published in MACS Service Reports expresses the views of the contributors and not neces-sarily that of MACS. Every attempt has been made to ensure

the accuracy of the content of MACS Service Reports. MACS, however, will not be responsible for the accuracy of the informa-tion published nor will MACS Worldwide be liable in any way for injury, labor, parts or other expenses resulting from the use of information appearing in MACS Service Reports.

March 2015 1 MACS Service Reports

Total Vehicle Climate and Thermal ManagementTM

©

When it comes to Electronic Service Information (ESI) resources, a couple of my favorite words are free and cheap. Although I’ve always been willing to spend money on in-formation and resources to diagnose and repair vehicles, if I fi nd there are no-charge or inexpensive tools and web resources available, I’m naturally interested in checking them out. I’m go-ing to guess you may also be of a similar mindset, so let’s take a bit of time to identify various internet resources that are out there to help us out, without breaking our bank accounts.

Today’s aftermarket information sources are an excellent value. Mitchell, Motor, ALLDATA, Moto Logic and Identi-

fi x (to name a few) are typically accurate and easy to use. On the other hand, the frequency of occurrences where these service information providers contain apparent errors and omissions is not small. In fact, the problem is great enough to motivate any good automotive aftermarket technician or shop owner to maintain those friendships with their contem-poraries at OEM dealerships in order to ask for the occasion-al ‘favor’ in getting the latest OEM information. This isn’t always practical, so there are a few solutions to help you fi nd the true OEM service information and other helpful web re-sources at reasonable prices. ■

March 2015 By Dave Hobbs, MACS Technical Correspondent

CYBER REPAIRS – HARNESSING THE POWER OF THE INTERNET IN YOUR REPAIR BUSINESS

ORIGINAL EQUIPMENT MANUFACTURERS: THE ULTIMATE ESI AUTHORITY

NASTFThe National Automotive Service Task Force

(www.nastf.org) contains a wealth of valuable ser-vice information. While NASTF’s main attraction is their OEM Service Matrix section containing live links to all passenger car and light duty truck OEM service websites, there is a lot more that they offer. NASTF’s site also has a wealth of other resources, such as a spreadsheet affording an easy to browse overview of pricing for various OEM ESI subscrip-tions. Pricing is sometimes as low as $20 for a week long OEM ESI subscription. A general rule of thumb for accessing OEM ESI is this: if you have spent more than one hour of frustration trying to find an accurate wiring diagram, component electrical pin chart, service theory of operation, description or specification with your aftermarket ESI, it’s worth the expense to pay for the OEM information in or-der to either find the accurate information you are trying to locate, or at least determine if the mistake

or omission is the same with the OEM information. Sometimes the apparent mistakes in aftermarket ESI systems are also in the OEM site.

An additional piece of valuable service informa-

tion available from NASTF is on the subject of J2534 reprogramming. On NASTF’s website, you’ll find a one hour free training video jammed with informa-tion on programming from leading industry experts. Experts like Michael Herron from Drew Technolo-gies (J2534 tool maker), Bob Augustine (director of training for Christian Brothers Automotive), and Bob Stewart (AC Delco) guide you through the electronic module programming maze to help you make sense of tool specifications and best practices for this very technical service endeavor. To watch this informative video, click on NASTF’s home page icon, then NASTF General Meetings and then click on NASTF YouTube Channel to watch this video and several others that are very helpful in educat-ing you on how the OEM’s are providing service

ALSO INSIDE THIS ISSUE:TECHNICIAN AND SHOP OWNER ASSOCIATIONS – WATCHING OUT FOR YOU! ........................................................... 6

March 2015 2 MACS Service Reports

information access to the aftermarket.

NASTF Vehicle Security InformationIf your shop has been in the frustrating position

of trying to sort out immobilizer key and key fob programming for VTD (Vehicle Theft Deterrent) equipped vehicles, technical info is provided by NASTF to help you. In many cases, locksmiths and mobile techs have the upper hand with practical-ity solely based on their specialization in this area. However, the mobile tech and / or locksmith solu-tion may not be practical depending on your loca-tion and situation. You can access the same infor-mation and utilize the same equipment required to program your customers’ immobilizer keys and key fobs. Quoting directly from NASTF’s website sec-tion on vehicle security:

“The NASTF Vehicle Security Professional (VSP) Registry is a service created from the NASTF Secure Data Release Model (SDRM), a project of the NASTF Vehicle Security Committee. SDRM is a data exchange system (see graphic) conceived and designed coopera-tively by automakers, independent repair, insurance and law enforcement communities; it allows the aftermar-ket to access security sensitive information related to automobiles, i.e. key codes, PIN numbers, immobilizer reset information, and similar types of information. The NASTF VSP Registry program allows access to securi-ty-related information while protecting the safety and security of consumers and the integrity of automobile security systems.”

OEM One StopThe link for NASTF is not exactly easy to remember. So

to make things simpler, NASTF has developed an OEM ESI redirect website that lists each OEM by their familiar logos. Go to the OEM1STOP website (www.oem1stop.com) and click on the vehicle manufacturer’s logo to get right to the site you need for electronic service information. When you click the OEM logo, you’ll have a simple choice of Mechanical, Col-lision or Hybrid. Collision is of course the obvious choice if you are looking for information on replacing a body panel. The hybrid category typically is limited to First Responder’s Guides. These free documents are sometimes helpful in de-termining where the high voltage safety service plug (discon-nect) is located on a hybrid electric or electric vehicle. What most techs should select is Mechanical to be linked straight to that OEM’s service information home page. At this point, things are pretty much the same as the OEM sites presented by OEM-1STOP’s parent website, NASTF. I occasionally visit NASTF to see what’s new but regularly visit OEM1STOP.com to make quick and simple selections to OEM ESI websites. I highly rec-ommend making this website a favorite on your work PC.

Each OEM presents their ESI home page with informa-tion on subscription pricing for service information (i.e. shop manual, wiring diagram, vehicle specifi cations) as well as J2534 computer reprogramming requirements and subscription costs. Toyota even has a category in their ESI section called NCF (New Car Features). As you select the vehicle model you are doing your research on, you’ll fi nd that besides wiring diagram, TSBs and the service manual, there are training documents for New Car Features containing valuable information you just won’t see anywhere else, ei-ther in the aftermarket or in the Toyota OEM service manual itself. It’s like opening up a Toyota factory training manual on-line. Kia and Hyundai do the same. Speaking of those OEMs, since I’m a fan of free I’ve been impressed in the past that Kia and Hyundai were free sites. The fi rst of last year however we watched Kia go to a modest fee schedule for ESI with Hyundai joining in, converting over to a paid site late in 2014.

Also regarding free, a special note must be made about Ford. By clicking on Ford, Lincoln or Mercury and then Me-chanical, you’ll be led to www.motorcraftservice.com.

Figure 2: NASTF’s Security Program: Today’s business model for after-market service access to OEM vehicle security systems. A clean criminal record and modest membership fee allows you to program keys just like the dealer or local locksmith. LSID stands for Lock Smith Identifi cation and NICB stands for National Insurance Crime Bureau.

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Figure 1: NASTF’s OEM matrix is an easy to use, alphabetically ar-ranged, live link chart that will put you in touch with most OEM ESI websites with a simple mouse click.

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March 2015 3 MACS Service Reports

Motorcraft ServiceA simple click from OEM1STOP, this Ford website

is absolutely aftermarket tech friendly with a cat-egory on the left side of their home page designated Non-Subscription Services, giving you the ability to pull up any Ford, Lincoln or Mercury’s owner’s manuals / owner’s manual supplements should the printed manual be missing from your customer’s glove box. We’ve all been in a position of trying to determine ex-actly how something is supposed to work before at-tempting to repair it. The old saying “If it’s not broke you can’t fix it” still applies in the year 2015. Take compressor operation for example. Years ago, when you pressed “Econ” on the HVAC head it meant the compressor would not be running – at all. Today, de-pending on whether the vehicle is a hybrid or not, the Econ button may mean the compressor runs, but runs less for fuel economy’s sake. On some GM stop/start hybrids and pre-2010 model year Ford hybrid SUVs with mechanical compressors, Econ may mean the gas engine shuts off at idle (to save fuel) and then starts back up during that idle situation when the evapo-rator temperature sensor’s value triggers the HVAC head to request A/C compressor activation, which of course requests a gas engine restart. On a hot day, the gas engine may run all the time, even if the vehicle is stopped in traffic. Knowing this can help you edu-cate your customer when either an A/C performance or fuel economy complaint is being discussed. Vehicle owner’s manuals, being PDF based documents, means you can even copy and paste sections into your repair order fields for record keeping or sharing with your customer via e-mail.

Free owner’s manual downloads are just one valuable (yet free) feature at Motorcraft’s ESI site. If you click on OBD II Theory & Operation, you’ll be directed to a page that contains a long list of downloadable PDF documents for Ford model years 1996 through the current 2015 model year. These PDF fi les are categorized by Gas, Hybrid and Diesel. At fi rst glance of the description OBD II Theory of Operation it would appear to be mundane, but these fi les ranging from 100 pages to over 400 pages are each VERY in-depth documents regard-ing anything you want to know about how Ford emissions and engine management systems work. If you are tackling a late model Ford thermostat monitor problem, for example, this document affords some real insight.

From Motorcraft Service Website – Detailed OBD II Thermostat Monitor Info

For the 2009 model year, the thermostat test has been en-hanced to reduce the time it takes to identify a malfunction-ing thermostat. The enhanced monitor includes a model which infers engine coolant temperature. During a cold start, when the thermostat should be closed, the monitor uses a model of ECT (Engine Coolant Temperature) to determine whether actual ECT should have crossed the (WUT) Warm Up Temperature threshold.

Once the ECT model exceeds the WUT threshold, af-ter a calibratable time delay, measured ECT is compared to the same WUT threshold to determine if ECT has warmed up enough. If ECT has warmed up to at least the WUT threshold, the thermostat is functioning properly. If ECT is too low, the thermostat is most likely stuck open and a code P0128 is set.

Figure 3: www.OEM1STOP.com is an easy way to fi nd all the various OEM ESI websites.

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Figure 4: Block diagram of an engine cooling system.

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Figure 5: Graph showing coolant temperature rise over time.

March 2015 4 MACS Service Reports

The WUT threshold is normally set to 20°F be-low the thermostat regulating temperature. There are some circumstances that could lead to a false diagnosis of the thermostat. These are conditions where the vehicle cabin heater is extracting more heat than the engine is making. One example where this can occur is on large passenger vans which have "dual" heaters; one heater core for the driver and front passengers and another heater core for the passengers in the rear of the vehicle. At very cold ambient temperatures, even a properly func-tioning thermostat may never warm up to regulat-ing temperature. Another example is a vehicle that is started and simply sits at idle with the heater on high and the defroster fan on high. There are two features that are used to prevent a false thermostat diagnosis. For vehicles with dual heaters, the WUT threshold is reduced at cold ambient temperatures below 50°F. For cases where the engine is not pro-ducing sufficient heat, a timer is used to track time at idle or low load conditions (e.g. deceleration). If the ratio of time at idle/low load versus total engine run time exceeds 50% at the time the fault determination is made, the thermostat diagnostic does not make a fault determination for that driv-ing cycle, i.e. "no-call".

GM Techlink – Awesome Mini Articles and Tech TipsNot everything OEM related is in traditional ESI

service manual format. Some resources are in the form of monthly service news publications like MACS Service Reports for example. In the world of OEM service for General Motors, that means Tech-link. The website http://sandyblogs.com/techlink/ is where you find it. I’ve been reading it for over 25 years and it seems to be as good today as it was back

in the beginning if you work on very many GM ve-hicles. There are great mini tech articles throughout each month’s edition, followed by a spreadsheet of the latest silver bullet fixes for GM vehicles. Here are some examples of what you will find for free.

Insuffi cient A/C Performance at Idle - June 5, 2013On some 2013 Chevrolet Sparks, the air condition-

ing duct temperature may be 10°F (5.6°C) warmer at idle, but is sufficient while driving.

Verify that the A/C pressures are within specifi-cations at idle according to the A/C Performance Chart in the appropriate Service Information. If A/C pressures and duct temperatures are not with-in specifications, perform the following:

1) Verify the proper refrigerant level is in the A/C system: 0.94 lbs (430 grams). If the refrigerant level is low, add GM-approved A/C dye to vehicles built before January 29, 2013, recharge the system to specification, evaluate, and perform an electronic and black light leak detection test. A/C dye began being added during assembly of the Spark at the plant on January 29, 2013.

2) If pressures at idle and slightly above (in-creased by 200 RPM) are the within 10 PSI (69 kPa) of each other, do not attempt any repairs or replace any parts at this time. GM Engineering is working on a repair to address this condition.

3) If the pressures are not within normal specifica-tions at idle but become normal slightly above idle (for example, at idle the low side pressure is higher than normal, i.e. 60 PSI (414 kPa) at 72°F (22°C), and then when the engine RPM is raised higher, i.e. 1500 RPM, the low pressure drops to within spec, i.e. 40 PSI (276 kPa), this indicates an internal compressor seal condition and the A/C compressor will require replacement.

Figure 6: The 2013 Chevrolet Spark has Manual A/C controls.

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ESI Tech Tip Hint: When searching for information via the web that is buried in a large document or website, use your menu bar to click on “Edit” and then “Find.” This allows you to type in a key word for what you are looking for in order to get right to the information you need.

March 2015 5 MACS Service Reports

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Figure 7: Each month’s GM Techlink ends with a summary such as this one listing the latest silver bullet fi xes (what to do and what NOT to do) for both passenger cars and light duty trucks.

Automotive Supplier Associations – Marketing or Informing?Why even bother with parts maker websites? Af-

ter all, Google gets you everything, right? While it seems at times that Google helps you find almost everything, it isn’t always quick to wade through website after website, which are often advertise-ment driven. You could Google a part supplier ’s name and peruse their website, but that can be time consuming and marketing riddled too. Industry as-sociations tend to be more to the point. While it’s true, automotive component manufacturers are the contributors of information to these organization’s websites, the organizations themselves keep the in-formation from being marketing oriented. Some of these are the same organizations that lobby Con-gress on behalf of the automotive aftermarket for both supplier and repair shop concerns.

Motor & Equipment Manufacturers Association – Great Filter and Fuel Pump Info

This website, like NASTF, sounds almost too mundane to bother looking at for a working techni-cian. However, this industry association has a sub-group called the Automotive Aftermarket Suppli-ers Association (AASA). Drilling down within that website is a tab entitled Councils, two of which are very helpful. The Filter Manufacturers Council has a wealth of information. Technical bulletins on top-ics ranging from coolant technology and color to air filters to diesel particulate filters are arranged in short but technically concise articles and bulletins (http://www.aftermarketsuppliers.org/Councils/Filter-Manufacturers-Council/TSBs-2).

If you’ve been bitten by the defective fuel pump bug, you’ll be glad to know that the Fuel Pump

March 2015 6 MACS Service Reports

TECHNICIAN AND SHOP OWNER ASSOCIATIONS – WATCHING OUT FOR YOU!

Mobile Air Conditioning Society (MACS) WorldwideAt the risk of sounding like a Sunday school

teacher trying to teach master theologians about the 10 commandments, I do need to make sure you’ve visited the MACS website lately to get the most technical information and the related benefits from it! Getting the most from being a MACS member does not mean simply reading the print publica-tions and attending the annual MACS convention and this fact will be quite apparent when you pe-ruse the www.macsw.org website.

609 Certifi cation – New for 2015Obviously the hot item here is the Section 609

Certification tab you are going to want to click on to download the latest study guide containing infor-mation regarding the new HFO-1234yf refrigerant. Vehicles are starting to pop up with yf, so it’s time to stay ahead of the game. The 60 page book is free to download, and not only includes technical and regulatory information, but also includes a handy

HVAC customer questionnaire and HVAC System Checklist to make copies of for your shop. The ac-tual test is available online for $20 and certification lasts for life.

Other MACS PublicationsDid you know that MACS publishes more than

just this monthly MSR? You are probably also aware of ACtion Magazine, but did you know both publi-cations are available digitally and in print versions? Same goes for the Section 609 Technician Certifica-tion Training Manual. The best place to start is on MACS’ website. While some areas of the site are open to the public, if you’re a member, your user-name and password gives you access to many of the Society’s archive pages. Among others you can find ACtion Magazines dating back to 2011, a MACS member directory and consumer information, the 2013 Field Survey, along with presentations ar-chived from the 2013, 2014 and 2015 annual train-ing events. MACS also publishes annual Mobile A/C Update books, along with several textbook titles which are popular with vo-tech schools and technician training centers. If you need help access-ing the MACS website, call the main office at (215) 631-7020.

MACS Training – Live Leader Ledor 24 Hours a Day On Your PC!

In addition to information regarding live leader led training either at the MACS Worldwide head-quarters in Lansdale, PA and the annual Mobile A/C Update training course held throughout the country, there is also a tab to click on to order their in-depth manuals on various HVAC disciplines. If it’s been very long since you have visited the MACS website, you may not be aware of their on-line training tab. This feature launches you into a web-page entitled MACS Online eLearning powered by AVI On Demand. This LMS (Learning Management System) allows MACS members to view all sorts of automotive training classes on-line, 24 hours a day at discounted prices. Topics from ASE Test Prep to HVAC system updates to drivability are available for the purchaser to view and interact with ques-tions and progress assessments for up to 1 year from date of purchase. There are even a few titles available from yours truly, including Mastering Hy-brid HVAC Systems along with several of my ASE test prep videos, including the ASE A7 HVAC Test Prep class.

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Figure 8: The new 609 certifi cation test for servicing mobile A/C system covers the R-12, R-134a and R-1234yf refrigerants among others. The training manual shown above is a must read for HVAC techs.

Manufacturers Council work group has invested a great deal of time and financial resources into sev-eral videos for both the parts specialist and the pro-fessional technician. The fuel pump videos, like the

tech bulletins on filtration, are free and very helpful (http://www.aftermarketsuppliers.org/Councils/FPM-WG/Videos/Repair-Professional-Videos). ■

March 2015 7 MACS Service Reports

RTI / Mahle Compressor Oil Chart One honorable mention of a simple A/C related

website I’ve used for years is the compressor oil chart from RTI. This downloadable PDF chart shows compressor illustrations and model numbers, along with OEM recommended oils and oil balancing pro-cedures. It’s a very quick, two page reference docu-ment that’s very easy to use compared to the “Eas-ter egg hunt” that some full ESI websites make of finding simple things sometimes.

international Automotive Technicians Network – iATNwww.iatn.net has over 75,000 members from 157

countries sharing 1.7 million years of auto repair experience. It was the first and is the largest on-line technician network. But even though iATN has been around since 1995, I’m still amazed at how many professional technicians are still unaware of this useful web based technical resource. Members have access to technical assistance from the iATN database, thousands upon thousands of image files (scope and scan tool captures), OEM training in-formation (including tons of free factory Ford, GM and Toyota info), as well as discussion databases archiving millions of messages and records shared between service professionals. Members must be

full time automotive service professionals. Since this is a “Golden Rule” type of organization, mem-bers must also be willing to occasionally help out other techs with problems before they post their own stubborn vehicle diagnostic problems online. There are two types of iATN memberships: free level and sponsor level. The free level allows you to post your tough diagnostic questions to other members and respond to your fellow techs with their posts. The sponsor level allows for use of ad-vanced features such as the new search engine that allows you to look at resolved and unresolved cases matching the symptoms and vehicle descriptions you enter into the iATN case search field. There is a video showing you the proper usage and benefit of the new search feature in case it’s been a while since you’ve logged in.

A variety of discussion groups on iATN include such topics as an HVAC discussion group, a forum for educators and a shop management discussion group.

Other resources include:1. Lambda Calculator (plug in your gas analyzer readings to get the Lambda number)2. OBD - II DTC Look Up3. Service Bulletin Search4. Trade Publications5. Fellow iATN Member Search

When a member submits a post for technical help, he or she is responsible for updating the post with further findings and closing the post with a detailed summary of what fixed the vehicle. You’ll receive e-mail reminders to update / close your open posts. Members are rated on timely closings of technical posts in order to keep the network relevant for oth-er technicians wishing to search for closed cases to help them with difficult to solve vehicle problems. You can refine the categories of vehicle diagnostics

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Figure 9: Mastering Hybrid HVAC Systems is one of several A/C top-ics available from AVI.

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Figure 10: This two page, easy to use compressor oil chart is free – just Google “RTI Compressor Oil Chart.”

March 2015 8 MACS Service Reports

MACS Service Reports is published monthly by the Mobile Air Conditioning Society Worldwide. It is distributed to members of MACS Worldwide and is intended for the educational use of members of the automotive air conditioning service and repair industry. Suggestions for articles will be considered for publication, however, MACS Worldwide reserves the right to choose and edit all submissions.

Unless otherwise noted, all photos/art by author.

Editors: Elvis Hoffpauir, Steve SchaeberProduction Designer: Laina CaseyManager of Service Training: Steve Schaeber

Mobile Air Conditioning Society WorldwideP.O. Box 88, Lansdale, PA 19446Phone: (215) 631-7020 • Fax: (215) 631-7017

Email: membership@macsw.org • Website: www.macsw.org

you are most interested in to limit the number of e-mails you receive daily listing technicians’ posts for help. When setting up your membership, don’t select every single category unless you want a LOT of e-mails every day!

These are just a few of the internet resources avail-able for you to begin an even more efficient process of harnessing the power of the web to drive your shop forward into the information age. If you know of some really good ones I missed, feel free to for-ward them on to me at david.a.hobbs@delphi.com.

Until next time, keep the mice clicking and the ratchets clacking!

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Figure 11: This sample iATN technician post shows the vehicle and problem description, the diagnostics and repairs already performed, the replies with suggestions from other techs along with what fi nally fi xed the vehicle. The highlighted text is what came up with the new search engine.

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Figure 12: Two iATN members share photos from two different ve-hicles on the HVAC discussion forum. Helpful photos like these, along with scan tool data screen captures and lab scope patterns are not un-common to fi nd from members who take their profession and helping others seriously.

Your Name: _______________________________

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Position/Title: ______________________________

Address: _________________________________

City: _____________________________________

State/Zip: _________________________________

Day Phone: ( ) _________________________

Fax: _____________________________________

E-mail: ___________________________________

Is this your fi rst MSR Test? (Circle one) YES NOAll members of MACS Worldwide may copy and distribute copies of this test to their company employees. The MACS Service Reports Training Program is only available to members of MACS and their company employees.

Certifi cate of Achievement - If you pass 8 tests each year (Aug. - Aug.), scoring at least 80% on each test, you qualify for a Certifi cate of Achieve-ment. If you qualify, MACS Worldwide will notify you by e-mail and you may order your Certifi cate of Achievement for $10.00.

Rec’d:

Score:

Init.:

1. A B C D2. A B C D3. A B C D4. A B C D5. A B C D6. A B C D7. A B C D8. A B C D9. A B C D10. A B C D

MACS Service Reports Quiz #MSR022015Based on February 2015 issue of MACS Service Reports

This test must be received within 30 days in order to be processed.Fill out the information at left, and circle the correct answer for each question in the box below.

Mail or fax your completed test to: MACS Worldwide, P.O. Box 88, Lansdale, PA 19446; Fax: (215) 631-7017

1. Technician A says a standard way to check the A/C clutch circuit is to hot-wire from the battery positive terminal to the clutch coil terminal. Technician B says if the clutch now engages, the problem is a defective relay. Who is right?

a. Technician A.b. Technician B.c. Both.d. Neither.

2. Technician A says the clutch relay had been a high-failure-rate item on systems with variable displacement compressors. Technician B says the relay had been a high-failure-rate item on some Japanese models. Who is right?

a. Technician A.b. Technician B.c. Both.d. Neither.

3. The clutch relay on 1994 Dodge Ram heavy-duty pickups was in a circuit that was tapped off the:

a. A/C pressure switch.b. horn relay.c. front control module .d. power steering pressure sensor.

4. The HVAC mode control on a 2006 Mer-cury Grand Marquis has airfl ow from the upper registers in normal cruising, but on accelerating up a hill, the airfl ow switches to the defrost outlets. The technician should:

a. replace the vacuum reservoir.b. replace the check valve.c. check the vacuum source to the mode

control and if good, replace the mode control.d. replace both the reservoir and check valve.

5. A 2001 Dodge Caravan with rear A/C has poor rear cooling, and the problem is traced to lack of refrigerant fl ow through the expansion valve to the rear unit, which has a solenoid valve. Technician A says the problem is with the solenoid, which should be replaced. Technician B says the expansion valve with solenoid can be removed and replaced with an expansion valve without the solenoid. Who is right?

a. Technician A.b. Technician B.c. Both.d. Neither.

6. The 2007 Honda Odyssey, in fl oor-only heat, did not produce adequate heat unless the upper level side registers were closed. Technician A says the mode control fl ap doors may not be sealing properly and should be checked for leakage. Technician B says the mode control actuators may be locking up early in their travel and this should be checked. Who is right?

a. Technician A.b. Technician B.c. Both.d. Neither.

7. A blend-air (temperature) actuator on a late-model General Motors car has been replaced but the new one doesn’t work. Tech-nician A says it should be initialized with the special functions menu on a Tech 2 scan tool.

Technician B says it should be initialized by removing the HVAC fuse for one minute. Who is right?

a. Technician A.b. Technician B.c. Both.d. Neither.

8. Some of the airfl ow in fl oor heat-only mode on a 2005 Toyota Tacoma V6 is bleeding through the defrost duct. This is:

a. normal.b. a leaking fl oor mode door.c. a leaking intermediate mode door.d. a warped HVAC case, a problem that could occur in hot, humid areas.

9. Technician A says the evaporator housing for the Ford “Panther” platform (Lincoln Town Car/Mercury Grand Marquis/Ford Crown Victoria) comes out from the engine compartment. Technician B says the retaining nuts for the case are acces-sible under the dashboard. Who is right?

a. Technician A.b. Technician B.c. Both.d. Neither.

10. The “Panther” models for which the factory specifi es replacement of the entire housing are:

a. all Lincoln Town Car.b. 2004-05 Mercury Grand Marquis and Ford Crown Victoria.c. 2010-11 Mercury Grand Marquis and Ford Crown Victoria.d. all of the above.