Operation CHARM: Car repair manuals for everyone.
Home >> Buick >> 1997 >> Skylark V6-3100 3.1L VIN M SFI >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Relays and Modules - Computers and Control Systems >> Engine Control Module >> Service and Repair >> PCM/EEPROM Replacement/Programming

PCM/EEPROM Replacement/Programming

PCM Installation:






PCM Servicing

Notice: In order to prevent possible Electrostatic Discharge damage to the PCM, Do Not touch the connector pins or the soldered components on the circuit board.

Service of the PCM should normally consist of either replacement of the PCM or EEPROM programming. If the diagnostic procedures call for the PCM to be replaced, PCM should be checked first to see if it is the correct part. If it is, remove the faulty PCM and install the new service PCM.

Notice: In order to prevent internal PCM damage, leave the ignition OFF when installing or removing the PCM connectors and disconnecting or reconnecting the power to the PCM (battery cable, PCM pigtail, PCM fuse, jumper cables, etc.).

Important: When replacing the production PCM with a service PCM, it is important to transfer the broadcast code and production PCM number to the service PCM label. Do not record on PCM cover. This will allow positive identification of PCM parts throughout the service life of the vehicle.

THE SERVICE PCM EEPROM WILL NOT BE PROGRAMMED. DTC P0602 indicates the EEPROM is not programmed or has malfunctioned.

Removal Procedure

Notice: Numbers in text correspond to numbered components in image.

1. Disconnect the negative battery cable.

2. Remove the right hand sound insulator.

3. Remove the PCM.

4. Remove the PCM connectors.

5. Remove the PCM access cover.

6. Remove the Knock Sensor (KS) module. Refer to Knock Sensor Module.

Installation Procedure

1. If a new PCM is being installed, install the KS module from the original PCM. Refer to Knock Sensor Module.

2. Install the access cover on PCM.

3. Install the connectors to PCM.

4. Install the PCM.

5. Install the right hand sound insulator.

6. Connect the negative battery cable. If a new PCM is being installed, program the EEPROM.

EEPROM Programming

1. Set-up - Ensure that the following conditions have been met:

^ The ignition is ON.

^ The Vehicle Interface Module (VIM) cable connection at the Data Link Connector (DLC) is secure.

2. If the PCM fails to program, check the GM Techline equipment for the latest software version.

3. Attempt to program the PCM. If the PCM still cannot be programmed properly, replace the PCM. The replacement PCM must be programmed.

Functional Check

1. Perform the On-Board Diagnostic System Check.

2. Start engine and run for one minute.

3. Scan for Diagnostic Trouble Codes (DTCs) using the scan tool.

4. If DTC P0325 sets, the KS module is not fully seated, is missing, or is faulty.

Crankshaft Position Variation Learn

The crankshaft position system variation compensating values are stored in the PCM non-volatile memory after a learn procedure has been performed. If the actual crankshaft position system variation is not within the crankshaft position system variation compensating values stored in the PCM, DTC P0300 may set (refer to "Diagnostic Aids" for DTC P0300).

The Crankshaft Position System Variation Learn Procedure should be performed if any of the following conditions are true:

^ DTC P1336 is set.

^ The PCM has been replaced.

^ The PCM has been reprogrammed.

^ The engine has been replaced.

^ The crankshaft has been replaced.

^ The crankshaft harmonic balancer has been replaced.

^ The crankshaft position sensor has been replaced.

Important: The scan tool crankshaft position system variation learn function will be inhibited if engine coolant temperature is less than 70°C (158°F). Allow the engine to warm to at least 70°C (158°F) before attempting the crankshaft position system variation learn procedure.

The scan tool crankshaft position system variation learn function will be inhibited if any powertrain DTCs other than DTC P1336 are set before or during the crankshaft position system variation learn procedure. Diagnose and repair any DTCs if set.

The crankshaft position system variation learn function will be inhibited if the PCM detects a malfunction involving the camshaft position signal circuit, the 3X reference circuit, or the 18X reference circuit.

^ If the scan tool indicates a problem with the Cam signal, refer to DTC P0341 CMP Sensor Circuit Performance.

^ If the scan tool indicates a problem with the 3X crank signal, refer to DTC P1374 3X Reference Circuit.

^ If the scan tool indicates a problem with the 18X crank signal, refer to DTC P0336 18X Reference Signal Circuit.

Procedure

1. Set the parking brake.

2. Start the engine and allow engine coolant temperature to reach at least 70°C (158°F).

3. Turn OFF the ignition switch.

4. Select the crankshaft position variation learn procedure from the scan tool special functions list.

5. Follow the instructions displayed on the scan tool. If the procedure is terminated, refer to Important above for instructions.

6. Observe DTC status for DTC P1336.

7. If the scan tool indicates that DTC P1336 ran and passed, the crankshaft position system variation learn procedure is complete. If the scan tool indicates DTC P1336 failed or not run, check for other DTCs. If no DTCs other than P1336 are set, repeat the crankshaft position system variation learn procedure as necessary.

PCM Password Learn Procedure

The password learn procedure is a follows:

1. Attempt to start the engine.

2. Leave the engine in the ON position. The theft system lamp will flash for 10 minutes.

3. When the theft system lamp stops flashing, start the vehicle.

4. Once the engine is running the password is successfully learned.

pro multis · About Operation CHARM