Check engine light not coming on 95 240sx

[dued]

I'm in the process of getting my car smogged in order to sell it. I passed all tests except for a check engine light. The tech mentioned that it failed because the check engine light does not come on when the key is switched on.

I don't remember the check engine light illuminating when in that position in the past, but I have been experiencing problems with the light every now and then while driving. The check engine light will randomly go on and start flashing, it will go on when I press my gas pedal, and go off when I let off??

:naw:

Help is much appreciated.

[dued]

Oh - I did take the car to a mechanic, he mentioned that the gauge cluster circuit was burned out or some b*llshit. I replaced the cluster with another one, same problem.

[bladetech8]

replacing the cluster isn't going to do you any well if you're not testing the bulb IN the cluster to make sure its not burnt out.. Also, irrc the ECU sends the signal to turn on the check-engine light, so you may want to make sure the ECU is pulling that PIN high (12v) or low (0v), dependent on how the bulb gets turned on from the ECU.

goodluck!

[dued]

replacing the cluster isn't going to do you any well if you're not testing the bulb IN the cluster to make sure its not burnt out.. Also, irrc the ECU sends the signal to turn on the check-engine light, so you may want to make sure the ECU is pulling that PIN high (12v) or low (0v), dependent on how the bulb gets turned on from the ECU.

goodluck!

Thanks for the info - I now have a different cluster in there with a different bulb, so it shouldn't be a bulb issue.

I'm not sure what PIN means.

[bladetech8]

PIN as in the electrical pins on the ECU plug (connects to ECU) or the ECU connector (located on the ECU itself)

[dued]

Bump for further input - I could really use some help with this.