Engine Management

DTC P1500:

DIAGNOSTIC TROUBLE CODE P15OO
BATTERY VOLTAGE TOO HIGH OR LOW

Symptom of fault
Possible driveablity problems

Conditions.
Engine speed >2000 rpm
+15 <8 V or >16 V for 30 seconds

NOTE: The fault diagnosis presupposes that the condition of the battery and its connections has been checked.

Diagnostic procedure
1. Connect an ISAT scan tool.

- Start the engine and run it at idling speed.
- Select the "BATTERY VOLTAGE" command on the ISAT menu "READ FUNCTIONS".

The ISAT must show 12.5 - 14.0 V.

2. Measure the battery voltage directly across the poles of the battery.
The voltage value must be 12.5 - 14.0 V.

- Compare the reading with the ISAT reading.

The difference must be <0.5 V.

- If the difference is <0.5 V, continue with step 4.
- If the difference is >0.5 V, disconnect grounding point G7P, clean the contact surfaces and refit, then repeat step 2.
- If the voltage difference is still >0.5 V, continue with step 3.

DTC P1500:

3. With the ignition switched OFF, connect a Break Out Box (BOB).

- Start the engine.
- Check battery voltage and ground connection by measuring voltage.
^ Batt + pin 1 ___________ <0.5 V.
^ Batt + pin 48 __________ <0.5 V.
^ Batt + pin 60 __________ <0.5 V.
^ Pin 24 Batt - __________ <0.1 V.
^ Pin 25 Batt - __________ <0.1 V.
- If any voltage value is incorrect, check and if necessary remedy the fault in the wiring.
- If the voltage values are correct, continue with step 4.

4. Erase the diagnostic trouble code and drive the car to check whether the DTC is generated again.

- If the diagnostic trouble code is registered, continue at "Procedure before replacing ECM".
- If the diagnostic trouble code is not registered, the action taken is correct. Otherwise the fault is intermittent in nature.