Thursday, 27 January 2011 10:12

Are You in the Diagnostics Business? ‘Yes’ is the Right Answer!

Written by Dan Espersen

Whether you like it or not, if you are in the business of repairing vehicles after an accident, you either are in, or will soon be in, the business of vehicle diagnostics. The proliferation of electronic components, data buses and components has forced the Collision Industry to invest in new equipment, specialized training and procedures. Consider this: only 10 years ago the average vehicle had 1-3 electronic control modules installed, controlling the engine, anti-lock brake system and perhaps the transmission. By contrast, the 2008 F-150 Ford Pickup truck had 20 control modules, 50 sensors, 40 actuators running on 3 data networks.  Some luxury vehicles have more than 70 electronic modules on-board.

The mechanical repair and diagnostic businesses have been updating their technologies continuously since 1981 to deal with these new technologies. Even in that sector many shops and technicians who were unwilling to acquire the skills and tools necessary to support the rapidly evolving industry have now shut down their operations. Many businesses have tried to “specialize” or diversify by establishing or offering brake or alignment services or possibly other specialized areas which did not have to get caught up in what many have called the “electronic revolution”. However, today there is virtually no system on the vehicle which is not touched somehow by these new electronically enhanced components.  So those who chose to ignore them or try to work around these systems, either had to scramble to equip themselves, or are no longer in that industry.


I’ll out-source these jobs
Up until now, many collision repair shops have had options to deal with the enhanced electronics on the vehicle. It boils down to two approaches: outsource or invest. Outsourcing or subletting, whichever you call it, has been attractive because it requires no up front investment in tools and training, and the costs can generally be passed to an invoice. However, it is difficult to achieve profit on this type of work as the workload and the cost can only be expensed on an invoice at face value, without the ability to up charge for these services. When diagnostics are done in-house, you are free from relying on the mechanical shop to perform the necessary diagnostics and you can then charge for this time, which in turn, could also be profitable for your shop.


This approach has become problematic, however. First, there is the time issue.  If a vehicle is disabled, there may be towing fees and time involved, which must be taken into account. Insurance companies don’t want to pay for rental cars for any longer than is necessary, and customers want their cars back. Second, while mechanical shops are very good at diagnosing problems which occur naturally on a vehicle, some aren’t so savvy when it comes to “collision-induced damage” as sometimes those symptoms may be foreign to them.

Third, because these types of necessary diagnostic steps and repairs are many times unknown at the time of the original estimate (based on visual inspection) there’s the added annoyance of having to request supplemental approvals for work to be done above and beyond the original estimate. Supplements often times, mean more parts need to be ordered, more time the vehicle is off the road and more time in your bay. or someone else’s.

What does it take to do the job right?
The reality is, at some point, which you’ll have to determine, you’re going to have to research and acquire the tools, training and information needed to deal with these complex problems. The good news is once you’ve geared up for it, you’ll reap the benefits of additional revenue for diagnostic time and associated components.

The first thing you will need is a diagnostic tool which can connect to the OBDII diagnostic port on any vehicle 1996 and newer and read and clear Diagnostic Trouble Codes (DTC’s). These tools range in price and functionality so you’ll want to determine how much you need to get started. The most basic handle what is commonly called “Generic OBDII” – these are the mandated codes and data which must be accessible from any vehicle 1996 and newer without a lot of fancy programming on the tool-designer’s part.  The good news is these are relatively inexpensive. The bad news is these regulations were designed to assist in diagnosing emissions-related issues on the vehicle.  So many vehicles won’t offer up ABS, Restraint system and other key information which is important to the collision repair business. If you are  repairing a lot of TPMS, Restraint and other associated systems, chances are you’ll need a diagnostic scan tool with more features (and higher cost). Research the various capabilities; even these more enhanced tools vary widely in price.

Regardless of which tool you purchase, it will provide you the code and sometimes a description of the code. Other scan tools may offer “troubleshooting tips” about the code — but for the typical failure of a sensor. These tips typically do NOT address the types of repairs a collision shop sees. So the best tool to supplement your diagnostic tool and its code readout capability is access to OE Information.

Access to OE information is important for a few reasons. Once a code has been identified, the code for the vehicle can be researched and the proper diagnostic procedures accessed. OE information sources include factory Technical Service Bulletins (TSB’s) which can save a lot of time and headaches as they’ll let you know if a component or diagnostic procedure has been “upgraded” since the original information was published.

An all too common situation
Let’s say you’re working on a 2010 Chevy Malibu. One of the items needing to be replaced is the driver’s seat assembly. As you begin to put the new seat hardware together you notice the airbag sensor connectors don’t match. You immediately suspect somehow you have the wrong item. Referring to that vehicle and operation in the OE information, however, reveals a Technical Service Bulletin which was issued and never carried out on this particular vehicle, which requires replacement of the connectors. The following TSB from ALLDATA’s Collision S3500 gives us a real-world example of the importance of this information:


Bulletin No.: 10-09-41-002A

Date: July 27, 2010

Subject: Intermittent Airbag Indicator with DTCs B0014 and/or B0021 Set (Replace Airbag Connector and Terminals, Reroute Airbag Harness)

2010 Chevrolet Malibu
2010 Pontiac G6
2010 Saturn AURA

This bulletin is being revised to update the Correction and Parts Information. Please discard Corporate Bulletin Number 10-09-41-002 (Section 09 - Restraints).

Some customers may comment on the intermittent illumination of the airbag indicator. Upon further inspection, DTCs B0014 and/or B0021 may be set.

This condition may be caused by terminals wearing within the body harness to seat airbag harness connectors X308 (driver side) and X309 (passenger side).

Replace the seat air bag harness to main body harness connectors with the service kit part number provided.

DO NOT replace the sensing and diagnostic module (SDM), side sensors or air bag modules.

Both driver and passenger seats must be repaired when this concern occurs. The service kit contains sufficient components to repair both seats connectors and attachment clips.

Connector Replacement
The service kit shown above is early production and does not contain the correct color wire seals.

Replace connectors on both driver and passenger seats, then reroute and attach the harnesses to the seat using the service kit.

1. Disable the SIR system. Refer to SIR Disabling and Enabling in SI.
2. Disconnect connector C308 (1) from under the driver’s seat cross-beam. The connector is accessible from the rear of the seat (2).

Only use hand tools to remove the seat to floor mounting bolts. If there are any problems with bolt removal, refer to Corporate Bulletin Number 10-08-50-002.

3. Remove the driver’s seat. Refer to Front Seat Replacement - Bucket in SI.

Note the wire colors on the seat airbag harness and body harness. Ensure that the wire colors are matched when installing into the new connector.

4. Cut both wires from the body harness connector and seat airbag harness connector as close to connector housing (1) as possible to minimize wire length loss.
5. Slide the conduit away and remove tape (1).

Use caution when stripping insulation. Take care not to cut through the wire strands.

6. Slide the wire seals onto all four leads back enough to enable removal of the insulation. Install the blue seals on the body harness and the white seals on the seat airbag harness. Strip the insulation off all four leads 5 mm (3/16 in). Align the seals with the wire insulation.
7. On the body harness, position two FEMALE terminals onto the wires. Caution must be used not to position the wire too far forward as it may interfere with the mating portion of the terminal. Crimp the terminals on to the bare wire using the J 38125-7 crimp tool, jaw E (1). Repeat the procedure using two MALE terminals on the seat airbag harness.
8. Position the wire seal to the terminal and crimp the seal and insulation using the J 38125-6 crimp tool, jaw 1 (1).
Avoid getting solder on the terminal end or overheating the terminal.

DO NOT use soldering equipment that is battery or electric powered. These types of soldering irons can induce voltage into the circuit, which may cause inflator module deployment and/or damage to electrical components. Use only the EL-28125-5 Ultra Torch or another butane fueled soldering iron when working on SIR circuits.

9. Solder all four terminals at the wire crimp.
10. Slide the two seat airbag harness terminals through the opening of the orange connector position assurance (CPA) (1).
Ensure that the appropriate wire colors match up (as noted in Step 4) when the connection is made between the seat airbag harness and body harness.

11. Slide all four terminals (2) into the appropriate connector body as shown above. Install the blue terminal position assurance (TPA) devices onto the connector ends.
12. Install the gray connector clip onto the appropriate connector body.
13. Add NyoGel 760 Lubricant, PN 12377900 (in Canada, use PN 10953529) to the terminals on both sides of the connections.
14. Wrap anti-abrasion electrical tape around the two exposed wires on the seat harness for a length of 30 mm (1.2 in) from the back of connector. Continue to wrap the tape around the back of connector.

Obtain “*Woven Polyester (PET) Electrical Tape” (Special Order PN RZ97156A00) from Kent Automotive. Refer to Parts Information below.
15. Slide the conduit back up. Wrap tape starting at the back of the connector and over the conduit for a length of a 130 mm (5 in).
16. Tape on the gray clip at 110 mm (4.33 in) from the back of the connector. Note that the clip orientation should be in-line with the retainer clip orientation on the connector.
17. Repeat the above procedure on the passenger seat.

Attach Drivers Side Harness to Seat
Follow the procedure below to re-route and attach the harness to the driver seat:
1. Insert the connector retainer clip into the rectangular attachment hole (1) on the driver seat as shown above.
2. Ensure that the service loop (2) faces towards the front of the seat.
3. Insert the tapped-on gray clip into the round attachment hole (3) as shown above.
4. Attach the existing black clip to the new seat suspension location (4).

Attach Passenger Side Harness to Seat
Follow the procedure below to re-route and attach the harness to the passenger seat:
1. Insert the connector retainer clip into the rectangular attachment hole (1) on the passenger seat as shown above.
2. Ensure that the service loop (2) faces towards the front of the seat.
3. Insert the tapped-on gray clip into the round attachment hole (3) as shown above.
4. Attach the existing black clip to the new seat suspension location (4).

Reinstall Seats
1. Install both the driver and passenger seats. Refer to Front Seat Replacement - Bucket in SI.
2. Make the connections between the seat airbag harness and the body harness.
3. Enable the SIR system. Refer to SIR Disabling and Enabling in SI
In the above example, the scan tool may have given a code even if the connectors could have been connected, and the access to OE information let us know how to properly repair the vehicle.
So next time someone asks if you’re in the Diagnostic business, what answer will you give?

Written by Dan Espersen and Ben Johnson. Ben Johnson is ALLDATA’s Senior Product Marketing Manager. Ben is a recognized technology leader in vehicle diagnostics with decades of driving diagnostics product development. Ben holds a degree in Business Administration.

©2011 ALLDATA LLC. All rights reserved. All technical information, images and specifications are from ALLDATA Collision. ALLDATA is a registered trademark and ALLDATA Collision is a mark of ALLDATA LLC. All other marks are the property of their respective holders.
Chevy and Malibu are registered trademark names and model designations of GM. All trademark names and model designations are being used solely for reference and application purposes.