CMP Sensor - Revised Electrical Schematic

File In Section: 6E - Engine Fuel & Emission

Bulletin No.: 81-65-43

Date: January, 1999

SERVICE MANUAL UPDATE

Subject:
Section 6E3 - Engine Controls - Revised Information in Camshaft Position (CMP) Sensor Electrical Schematic; Additional Cause of DTC P1300

Models:
1996-97 Chevrolet Geo Prizm
with 1.6L, 1.8L Engine (VINs 6, 8 - RPOs L01, LV6)

This bulletin updates Section 6E3 of the 1996 Geo Prizm Service Manual Book 2 GMP/96-S-2 and Section 6E3 of the 1997 Geo Prizm Service Manual Book 2 GMP/97-S-2.

^ Some owners may experience a DTC P1300, MIL illuminated, the engine still starts and runs. Inspect the vehicle for an EFI relay that is staying ON after the ignition is turned OFF. If the EFI relay remains ON, after the ignition switch is turned OFF, the ECM/PCM remains active and expects to see ignition system fail-safe signals, even though the engine is not running. The ignition system fail-safe circuit diagnostic will set a DTC P1300 and illuminate the MIL on the next ignition cycle. Correct the operation of the EFI relay in order to eliminate the DTC P1300.

^ The wire connections from the ECM/PCM to the Camshaft Position (CMP) sensor at the distributor pigtail connector are shown reversed from actual in the electrical schematics in section 6E3. The wiring of the CMP sensor circuit is as follows:

- The WHT wire from ECM/PCM terminal C3-17 connects to the WHT/8LK wire in the distributor electrical connector cavity 2.

- The BLK wire from ECM/PCM terminal C3-5 connects to the GRN wire in the distributor electrical connector cavity 1.