P1500

BATTERY VOLTAGE TOO HIGH OR TOO LOW.





Fault Symptom.
CHECK GEARBOX indicator lamp on. The system's emergency operation program has been activated.

Conditions.
Battery voltage is continually lower than 9 V or higher than 16 V for longer than 0.5 seconds.





Procedure.
1. Check the transmission control module's power supply

- Connect the ISAT scan tool.
- Start the engine and run it at idling speed.
- Select "READ FUNCTIONS".
- Select "BATTERY VOLTAGE". The ISAT scan tool should show a reading of 12.5-14.0 V.

Is the voltage reading OK?

YES: Proceed to point 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 in the electrical system and then proceed to point 6.





3. Check the voltage difference

Compare the voltage with the ISAT scan tool reading. The difference should be less than 0.5 V.

Is the difference less than 0.5 V?

YES: Proceed to point 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 ISAT scan tool.
- Start the engine and run it at idling speed.
- Select "READ FUNCTIONS".
- Select "BATTERY VOLTAGE". The ISAT scan tool 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: Proceed to point 6.





5. Check the transmission control module's ground connection and power supply

- Connect a BOB.
- Start the engine and run it at idling speed.
- Connect a voltmeter to
^ pin 17 and B+: <0.5 V.
^ pin 18 and B+: <0.5 V.
^ pin 22 and B-: <0.1 V.
^ pin 35 and B-: <0.1 V.

Are all voltage readings OK?

YES: Continue with point 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.

Has the diagnostic trouble code recurred

YES: Continue as described under "Before Changing An Electronic Control Module". Before Changing A Control Module
NO: The remedial action taken was correct.