Lumina V6-191 3.1L VIN T MFI (1993)
Engine Control Module: Service and Repair
Federal Emissions
Computer
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, the PROM must be removed from the Computer being replaced and transferred to the new unit.
REMOVAL:
1.
Disconnect battery ground cable.
2.
Remove coolant tank reservoir.
3.
Remove ECM mounting hardware.
4.
Disconnect connectors from the ECM.
5.
Remove ECM from the engine compartment.
6.
Transfer PROM unit.
INSTALLATION:
1.
Re-connect connectors to the ECM.
2.
Install ECM mounting hardware.
3.
Install coolant tank reservoir.
4.
Re-connect battery ground cable.
FUNCTIONAL CHECK:
1.
Turn the ignition "ON."
2.
Enter diagnostics.
a.
Allow Code 12 to flash four times to verify no other codes are present. This indicates the PROM is installed properly and the ECM is
functioning.
b.
If trouble Codes 41, 42, 43, or 51 occur, or if the "SERVICE ENGINE SOON" light is "ON" constantly with no codes, the PROM is not fully
seated or is defective. If not fully seated, press firmly on the ends of the PROM.
