Why does the check engine light not illuminate with the key turned on?
I have a problem that the check engine light on my Grand am is not lit up when the ignition is on ,but the engine is not started. I need this to work to pass the emissions test.
Is there a bulb I can replace?
Before tearing out the cluster to replace a bulb, check fuses. I believe there’s one in the left I/P fuse block labeled IPC/BFC ACC.
Is this the fuse block that is located inside the car or is there another fuse block located under the hood?
There could be a fuse problem but I think the ECU provides power to it. I suggest you check the fuses in the dash and under the hood anyways. If the fuses are ok the trouble is hopefully just with the connection to the bulb and just cleaning the connections will fix the trouble. The bulb could also be burned out or for the worst case, the ECU may have an internal problem with the CEL light circuit and you will need a replacement ECU or have yours repaired.
If you run out of things to do stop by AutoZone and see if it is still possible to connect with the cars “computer”. If you are able to communicate with the computer it would be logical to direct your search to other reasons for the non illuminated “check engine” light(instead of computer failure). I never have tried to read codes on a car whose “check engine” light won’t come on so I really don’t know what to expect here,interesting.
I did locate the IPC/BFC ACC fuse and it did look burnt so I changed it but the service engine light still won’t illuminte when I turn the key. Is there a bulb is it LED. I did call a dealership and I was told that its LED but I’m not so sure that they are being honest. I did go to Auto Zone and they plugged into the computer and did get a cam sensor position code but in that case I would think that the service engine light would have to illuminate to tell you that there is a problem.
Power is provided by the fuse, the pcm grounds the circuit to light the light. You’ll need to get a manual with a good wiring diagram illustration like a Haynes manual. The first thing I would do since we know the fuse is good, is to find the wire coming from pcm for the light. With key on, ground wire to check for bulb operation. If it lights, I would suspect a bad pcm, if it doesn’t light, there’s a wiring problem most likely. Unless the light has been on for years and burned out, I really doubt it’s a bulb. And from what I can recall about these clusters, the bulbs can’t be replaced.
I did pull the cluster and there is a bulb for the service engine light which was burnt out so I replaced it but it still wouldn’t lite up so i took a test lite and checked for power where the lite plugs in and received very little current. Any ideas as to why this would happen?
The IPC/BFC ACC fuse gets its power from ignition switch. Turn key on and make sure you have good voltage at fuse. If you do, but it’s still low at cluster connector then there’s a wiring problem. If voltage is low at fuse, I would suspect bad ignition switch. I suppose one thing you could do for a test is to use a jumper wire wirh a small pin attached to it. turn ignition on and with jumper wire attached to battery positive. Be very careful not to touch a ground and touch pin to fuse and see if CEL lights. That’ll tell you the integrity of the wiring.