P1500

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

P1500

-	Connect the diagnostic tool.

-	Start the engine and run it at idling speed.

-	Select "READ FUNCTIONS".

-	Select "BATTERY VOLTAGE". The diagnostic tool should read 12.5-14.0 V.

Is the voltage reading OK?

yes

Continue with step 6.

no

Continue with step 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 step 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 diagnostic tool reading. The difference should not be greater 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 diagnostic tool.

-	Start the engine and run it at idling speed.

-	Select "READ FUNCTIONS".

-	Select "BATTERY VOLTAGE". The diagnostic tool should read 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 • 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 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.