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Home >> Saturn >> 1991 >> SL L4-1.9L SOHC VIN 9 >> Repair and Diagnosis >> Powertrain Management >> Relays and Modules - Powertrain Management >> Relays and Modules - Computers and Control Systems >> Engine Control Module >> Technical Service Bulletins >> Recalls >> Recall - Powertrain Control Module Replacement >> Service Procedure >> Diagnostic Differences
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Diagnostic Differences

Along with the campaign, many changes have been made to the diagnostic system. The following changes can be found in the "1991-1994 Service Manual."


Automatic Transaxles

Code 19 (6x Signal Fault) replaces Information Flag 67 (6x Signal fault).

Code 46 (Power Steering Pressure Circuit) has been calibrated out and power steering switch functionality will be done by the PCM.

Transaxle Information Flags 82 (Temperature Signal Unstable) and 91 (DLC Serial Communication Link Interrupt) will no longer be active.

Closed loop operation and Long Term Fuel Trim 3 will function like 1992 model year vehicles.

The malfunction indicator (MIL) lamp (SES telltale lamp) will be off during PDT/SSS communication.


Manual Transaxles

Code 19 (6x Signal Fault) replaces Information Flag 67 (6x Signal Fault).

Code 46 (Power Steering Pressure Circuit) has been calibrated out and power steering switch functionality will be done by the PCM.

Spark adaptives, long term fuel trim cells, closed loop operation and Malf history buffers will function like 1994 model year vehicles.

The malfunction indicator (MIL) lamp (SES telltale lamp) will be off during PDT/SSS communication.
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