With Integrated Fault-Diagnosis System (Flash Codes): 12242

Diagnostic procedure

If diagnostic trouble code 45691/25691 is generated simultaneously, it is advisable to deal with that trouble code first.

1 Remove the mass air flow sensor from the air cleaner.




2 Start the engine, warm it up to mm. 6500 (150°F), and run it at idling speed. Rev the engine up to 2,500 rpm, release the accelerator and run the engine at idling speed again.

3 Switch off the ignition and observe the filament (hot wire). It should glow brightly for about 1 sec. after about 20s (4s for LH 2.2). If it does not, go to point 4.




4 Unplug the connector from the mass air flow sensor. Start the engine and rev it up to 2,500 rpm. Release the accelerator and run the engine at idling speed. Switch off the ignition. Check that 4 V is present across pin 4 of the mass air flow sensor connector (pin 1 on mass air flow sensors of aluminium) and a good ground.

If it is, see point 5.

If it is not, see point 7.




5 Check the lead between pin 5 of the mass air flow sensor connector (pin 2 for a mass air flow sensor of aluminium) and pin 87B of the main relay. Also check the operation of the relay and the ground lead from pin 1 (or pin 4) to the engine grounding point.

6 If voltage is present, change the mass air flow sensor.




7 Plug the Breakout Box into the car's wiring harness (LH control module not connected). Check the mass air flow sensor's wiring between pin 4 (or pin 1) and pin 8 of the Breakout Box.

8 If the wiring is OK, change the control module.