Reading and Clearing Diagnostic Trouble Codes

Diagnostic Trouble Code (DTC) Table:

NOTES:
1. Diagnostic Trouble Code (DTC) 52 indicates that the keep alive, or "long term," memory in the IPC has been reset. It is a normal occurrence whenever power or ground is removed from the IPC, such as anytime the battery has been disconnected and reconnected. When this DTC is current, IPC memory is reset to the default values for DATE/TIME, EST TIME ARRIVAL, ELAPSED TIME, AVE FUEL ECON, FUEL RANGE, AVE SPEED, TIME 10 DEST AND DIST TO DEST. If DTC 52 sets without a battery disconnect, ensure good terminal contacts at power feed terminal DIS, and ground terminals C12, D12 and B10. If connections are good, the IPC must be replaced. The IPC should be serviced by an authorized Delco repair station, which will require vehicle VIN, mileage (if known) and option information. Consult the most recent service information for routing the IPC to a Delco Repair Center.
2. DTCs 70, 71, 75, 80 and 81 indicate that the IPC EPROM is not being read correctly by the IPC. The EPROM stores and verifies history DTCs, running resets, oil change data, trans fluid change data, vehicle option content, odometer and vehicle ID number. "ERROR" will be displayed in the place of the mileage on the IPC while DTC 70 is set. Verify proper terminal contact on connectors C1 and C2. If connections are good, the IPC must be replaced. The IPC should be serviced by an authorized Delco repair station, which will require vehicle VIN, mileage (if known) and option information. Consult the most recent service information for routing the IPC to a Delco Repair Center.
3. DTC 74 indicates that the IPC has detected invalid data or loss of communications with its internal Real-Time Clock (RTC). Verify proper terminal contact on connectors C1 and C2. If connections are good, the IPC must be replaced. The IPC should be serviced by an authorized Delco repair station, which will require vehicle VIN, mileage (if known) and option information. Consult the most recent service information for routing the IPC to a Delco Repair Center.
4. DTC 73 indicates that the IPC's Real-Time Clock has detected a battery disconnect. The DAYTIME data will revert to its default value of JAN 1 1993 12:00 p.m. In addition, the IPC will assume TRIP COMPLETE trip monitor status, reset ELAPSED TIME, FUEL ECON, AVG SPEED and OIL/TURNS FLUID CHANGE data, and invoke the CONFIRM TIME & DATE display on the DIC. If DTC 73 sets without a battery disconnect, ensure good terminal contacts at power feed terminal D15, and ground terminals C12, D12 and B10. If connections are good, the IPC must be replaced. The IPC should be serviced by an authorized Delco repair station, which will require vehicle VIN, mileage (if known) and option information. Consult the most recent service information for routing the IPC to a Delco Repair Center.