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Home >> Buick >> 1994 >> Regal V6-191 3.1L VIN M SFI >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Engine Control Module >> Service and Repair
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Engine Control Module: Service and Repair

Powertrain Control Module Installation:




Removing/Replacing Knock Sensor Module:




Knock Sensor Module - Removing From PCM:






NOTE:
- When replacing a production Computer with a service Computer, transfer the broadcast code and production number from the production unit to the service unit. Also during replacement, knock sensor module must be removed from the computer being replaced and transferred to the new unit.

CAUTION:
- These units do not have a replaceable PROM. An Electronically Eraseable Programmable Read Only Memory (EEPROM) is built into the PCM. The EEPROM may be a photo-sensitive type (program will be erased if exposed to light). These units must be programmed using General Motors "TECHLINE" terminal equipment. The replacement PCM is supplied without an EEPROM program. If this equipment is not available for your use, DO NOT attempt to replace PCM.



REMOVE OR DISCONNECT
- Disconnect battery ground cable.
- Coolant reservoir.
- PCM mounting hardware.
- Connectors from the PCM.
- PCM from the engine compartment.
- Remove the new PCM from its packaging and check the service number to make sure it is the same as the defective PCM.
- Access cover from PCM.
- Remove knock sensor module from PCM (see illustration).

INSTALL OR CONNECT
- Knock sensor module into PCM (see illustration).
- Access cover to PCM.
- PCM into the engine compartment.
- Connectors from the PCM.
- PCM mounting hardware.
- Coolant reservoir.
- Battery ground cable.
- Reprogram PCM using "Techline" or equivalent tool.



FUNCTIONAL CHECK:

1. Turn the ignition ON.
2. Enter diagnostics.
^ Code 12 should flash. This indicates the PCM is functioning.
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