WIS Document: 4635

| | P1500 Battery voltage too high or too low. Fault symptom CHECK GEARBOX indicator lamp on. The system's emergency operation program has been activated. Condition Battery voltage is continually lower than 9 V or higher than 16 V for longer than 0.5 seconds. Diagnostic procedure 1 Check the transmission control module's power supply | - | Connect the Scan tool diagnostics instrument. | - | Start the engine and run it at idling speed. | - | Select "READ FUNCTIONS". | - | Select "BATTERY VOLTAGE". The diagnostics instrument should show a reading of 12.5-14.0 V. Is the voltage reading OK? | yes Continue with step 6. | no Continue with point 2. 2 Check the battery voltage Take a voltage reading across the battery terminals. A reading of 12.5-14.0 V should be obtained. Is the voltage reading OK? | yes Continue with point 3. | no Continue fault diagnosis as described in Service Manual 3:1 "Electrical system" and then proceed to point 6. 3 Check the voltage difference Compare the voltage with the diagnostics instrument reading. The difference should be less than 0.5 V. Is the difference less than 0.5 V? | yes Continue with step 6. | no Continue with point 4. 4 Check the grounding point | - | Disconnect the cables from grounding point G34P (LHD) or G33S (RHD), clean the contact surfaces and reconnect the cables. | - | Connect the Scan tool diagnostics instrument. | - | Start the engine and run it at idling speed. | - | Select "READ FUNCTIONS". | - | Select "BATTERY VOLTAGE". The diagnostics instrument should show a reading of 12.5-14.0 V. Is the difference in voltage still more than 0.5 V? | yes Continue with point 5. | no Continue with step 6. 5 Check the control module's connection to ground and power supply | - | Connect BOB. | - | Start the engine and run it at idling speed. | - | Connect a voltmeter to &bull; pin 17 and B+<0.5 V. &bull; pin 18 and B+<0.5 V &bull; pin 22 and B-<0.1 V &bull; pin 35 and B-<0.1 V Are all voltage readings OK? | yes Continue with step 6. | no Investigate the cause and rectify the fault. Continue with point 6. 6 Final check Clear the diagnostic trouble code, drive the car on test at varying engine loads and speeds for 5 minutes and check whether the diagnostic trouble code recurs. Does the diagnostic trouble code recur? | yes Continue with . | no The remedial action taken was correct.