DIAGNOSIS AND TESTING - DOOR MODULE
Any diagnosis of the door module should begin with the use of the DRB III(R) diagnostic tool. For information on the use of the DRB III(R), refer to BODY DIAGNOSTIC PROCEDURES .
For complete circuit diagrams, refer to POWER DOOR LOCKS for the appropriate wiring information.
OBTAINING DTC'S USING SCAN TOOL
- Connect the scan tool to the data link (diagnostic) connector. This connector is located in the passenger compartment; at the lower edge of instrument panel; near the steering column.
- Turn the ignition switch on and access the "Read Fault" screen.
- Record all the DTC's and "freeze frame" information shown on the scan tool.
- To erase DTC's, use the "Erase Trouble Code" data screen on the scan tool. Do not erase any DTC's until problems have been investigated and repairs have been performed.
DIAGNOSIS AND TESTING - MEMORY HEATED SEAT ADJUSTABLE PEDAL MODULE
In order to obtain conclusive testing of the memory heated seat adjustable pedal module, the Programmable Communications Interface (PCI) data bus circuit and any components that provide inputs to the module must be checked.
The most reliable, efficient, and accurate means to diagnose the module requires the use of a DRB III(R) scan tool and the Service and BODY DIAGNOSTIC PROCEDURES articles. The DRB III(R) scan tool can provide vital information to the technician trying to find a problem with the module. Diagnostic logic software is built into the memory heated seat adjustable pedal module to help the person trying to locate the problem by the most efficient means possible. Anytime a problem is suspected, a DRB III(R) scan tool should be obtained and used to retrieve any stored fault codes in the memory heated seat adjustable pedal module. If diagnostic fault codes are present in the module, record them on a piece of paper immediately before proceeding any further. Then, use these fault codes to identify the problem by verifying the fault code. Example, If the module records "DRIVER SEAT HEAT OUTPUT OPEN" fault, locate the diagnostic procedure for this code in BODY DIAGNOSTIC PROCEDURES and follow the flow chart until the specific problem is located and resolved. Once the problem is corrected, erase the stored fault code using the DRB III(R) scan tool and verify correct heated seat system operation. If the heated seat system appears to be functioning correctly, verify that there are no other stored codes in the module and return the vehicle to service.
If the fault code could not be verified, such as not finding anything wrong when following the diagnostic flow chart in the BODY DIAGNOSTIC PROCEDURES article. This is a good indication that a INTERMITTENT problem may be present. You must than attempt to find the intermittent problem, such as moving the heating element within the seat while testing continuity or wiggling the wire harness's/electrical connectors under the seat while testing continuity. Always, eliminate all other potential problems before attempting to replace the memory heated seat adjustable pedal module.
For complete circuit wiring diagrams, refer to POWER SEATS .
PRELIMINARY TEST
Before testing the individual components in the suspect system, check the following
- Using the DRB III(R) scan tool, check the memory heated seat adjustable pedal module (MHSAPM) for any stored fault codes. Record these codes on paper for reference and resolve using the «BODY DIAGNOSTIC PROCEDURES»(ref-247415) article.
- Check the vehicles battery open-circuit voltage and charging system performance. If the vehicles electrical system is defective or weak it may not be suppling sufficient voltage to operate the system in question.