The approved procedure for diagnosing all powertrain control system faults is included in the Strategy Based Diagnostic Flow . You must perform the preliminary checks and the Powertrain On-Board Diagnostic (OBD) System Check in order to successfully diagnose and repair the powertrain systems.
Important: Use a scan tool to in order to clear the diagnostic trouble codes (DTCs) from the powertrain control module (PCM) memory.
The PCM can have a failure which can affect only one circuit. Follow the approved diagnostic procedures in order to determine which circuit has a problem and where the problem is located. If a diagnostic table indicates that the either PCM connections or the PCM is the cause of a problem, you replace the PCM is replaced but the problem still exists, one of the following conditions may exist:
| • | The electrically erasable programmable read-only memory (EEPROM) program is not correct for the application. |
| • | Incorrect components may cause a malfunction and may or may not set a DTC. |
| • | The problem is intermittent and the problem is not present at the time the that you diagnosed the system. In this case, refer to the Symptoms portion of the manual. Carefully inspect all suspected components and all wiring that is associated with the affected system. |
| • | The problem is caused by a shorted solenoid, relay coil, or harness. The PCM turns the solenoids and relays ON and OFF via internal electronic switches called drivers. Each driver is part of a group of seven output driver modules. A shorted solenoid, relay coil, or harness will not damage the PCM but will cause the solenoid or the relay to be inoperative. |
