P1510

IDLE AIR CONTROL VALVE





Fault Symptoms.
Low, high or hunting idle speed.
Idle speed sensitive to load changes.

Conditions.
P1510
^ Engine speed higher than 80 rpm.
^ Battery voltage 7.5 to 17 V.
^ Shorting to battery positive (B+).

P1513
^ Engine speed higher than 80 rpm.
^ Battery voltage 7.5 to 17 V.
^ Shorting to ground.

P1514
^ Engine speed higher than 80 rpm.
^ Battery voltage 7.5-17 V.
^ Open circuit.

P1551
^ Engine speed higher than 80 rpm.
^ Battery voltage 7.5 to 17 V.
^ Open circuit.

P1552
^ Engine speed higher than 80 rpm.
^ Battery voltage 7.5 to 17 V.
^ Shorting to ground.

P1553
^ Engine speed higher than 80 rpm.
^ Battery voltage 7.5 to 17 V.
^ Shorting to battery positive (B+).





Diagnostic Help.
The idle air control valve can be activated with the ISAT scan tool.
- Select "ACTIVATE".
- Select "IAC VALVE".

This command activates the valve at a frequency of 0.5 Hz for 30 seconds.

Check The Wiring.
Intermittent faults may occur as a result of temporary short circuits and breaks in the wiring. Jiggle the wiring at several points and in different directions to ascertain whether the wiring harness, including any connectors, is causing the trouble. Observe the multimeter, ISAT scan tool or test lamp while doing this.





Diagnostic Procedure.
1. Check the idle air control valve's power supply
- Unplug the valve's 3-pin connector.
- Turn the ignition switch to the ON position.
- Connect a test lamp to pin 2 and battery negative (B-).

The test lamp should light up.

Test lamp on?

YES: Continue with point 2.
NO: Repair or replace the lead between the 3-pin connector and crimped connection J128.
Then continue with point 3.

2. Check the control module's outputs to the idle air control valve
- Connect a test lamp to battery positive (B+) and pin 1 of the female connector.
- Connect the ISAT Scan Tool.
- Turn the ignition switch to the ON position.
- Select "ACTIVATE".
- Select "IAC VALVE".

The test lamp should flash at a frequency of 0.5 Hz for 30 seconds.

- Repeat the procedure above with the test lamp connected to battery positive (B+) and pin 3 of the female connector.

The test lamp should flash at a frequency of 0.5 Hz for 30 seconds.

Did the test lamp flash in both cases?

YES: Change the idle air control valve and continue with point 3.
NO: Check the lead in question and repair or replace it if necessary. Then continue with point 3.





3. Final check
- Clear the diagnostic trouble code.
- Implementation of driving cycle:
^ Drive the car at varying engine loads and rpm for 5 minutes.
- Evaluation of driving cycle:
^ Check whether the diagnostic trouble code has recurred.

Has the diagnostic trouble code recurred?

YES: Continue as described at "Before Replacing a Control Module". Component Tests and General Diagnostics
NO: The steps taken to rectify the fault were correct.