94 RENR5042-02 Troubleshooting Section G. Measure the resistance between terminal P2-80 and the engine ground. Repair: Repair the wire and/or the connector, when possible. Replace parts, if necessary. Verify that the problem is resolved. H. Measure the resistance between terminal P1-2 (+5 V Supply) and all of the remaining terminals on the P1 connector. STOP. Test Step 8. Check the +5 V Supply at the ECM a. Measure the resistance between terminal P1-2 and the engine ground. Expected Result: A. Remove terminal 72 (+5 V Supply) from the P2 connector. Install a wire jumper with socket terminals on both ends into P2-72. Each resistance measurement indicates an open circuit. B.
Connect ECM connectors J2/P2. Results: C. Remove terminal 2 (+5 V Supply) from the P1 connector. Install a wire jumper with socket terminals on both ends into P1-2. OK – Each resistance measurement indicates an open circuit. Proceed to Test Step 7. D. Connect ECM connectors J1/P1. Not OK At least one of the resistance measurements does not indicate an open circuit. A +5 V supply wire has a problem. There may be a problem with a connector. E. Turn the keyswitch to the ON position. F. Measure the voltage between the wire jumper in P1-2 and the engine ground. Repair: Repair the wire and/or the connector, when possible. Replace parts, if necessary. Verify that the problem is resolved. G.
Measure the voltage between the wire jumper in P2-2 and the engine ground. STOP. H. Turn the keyswitch to the OFF position. Test Step 7. Check the +5 V Supply and the Sensor Common for an Open Circuit I. Restore both wires to the original configuration. Expected Result: A. Install a wire jumper between terminals P2-72 (+5 V Supply) and P2-3 (Sensor Common). Both voltage measurements are 5.0 ± 0.2 VDC. B. Install a wire jumper between terminals P1-2 (+5 V Supply) and P1-3 (Sensor Common). Results: OK Both voltage measurements are 5.0 ± 0.2 VDC. Note: Wiggle the harness during the following measurements in order to reveal any intermittent short condition. Repair: Clear all diagnostic codes.
Check for active diagnostic codes. If the problem is intermittent, refer to Troubleshooting, “Electrical Connectors - Inspect”. C. Measure the resistance between terminals A and B at the harness connector for each pressure sensor. Expected Result: STOP. Each resistance measurement is less than ten Ohms. Not OK At least one voltage measurement is not 5.0 ± 0.2 VDC. Results: Repair: Replace the ECM. Refer to Troubleshooting, “Replacing the ECM”. OK – Each measurement is less than ten Ohms. Proceed to Test Step 8. STOP. Not OK – At least one resistance measurement is greater than ten Ohms. The +5 V supply wire or the return wire has excessive resistance. There may be a problem in a connector.