Rep Power: 0

02 honda civic LX. my civic will not pass smog because the check engine light does not come on. i have asked many people around me and know one seems to know why this is happening. ive checked the fuses, taken the cluster off and checked the lights, but i guess the check engine light is LED and a part of the circuit board. do i just need to buy a new cluster, or is it something with the computer, any help would be greatly appreciated!

 
Rep Power: 518

If you REALLY want to check stuff...

The PCM grounds pin E31 (green/orange wire) to turn on the CEL, connector pin B21 at the cluster connector.
(There is also a harness connector C453 in the middle of this circuit, so check continuity to make sure there isn't an open in this connector or the wiring.)

In the cluster, the CEL is an LED. Each LED uses a resistor on the hot side. Either one could be faulty. Could be poor solder joints on the circuit board too, usually simple fix to replace pieces or resolder the joints if you can solder small stuff.

There aren't schematics for the circuit board, so you'd have to follow each trace yourself.

A dealer or a shop would probably want to replace the entire gauge cluster.

HTH

 
Rep Power: 0

thanks for the response, unfortunately that sounds a lil out of my league. i can do basic repairs, but electrical is always been a lil tough for me, batterys and alt/starters are about it. do u think replacing the cluster would solve the problem, or is there a possibility that there is another problem?

 
Rep Power: 518

That's an expensive thing to guess at.
I don't make my money guessing.


You had the cluster out and apart far enough to see it uses an LED, but NOW you got scared?

Can you obtain and operate a volt/ohm meter? Backprobe?
See if that wire gets grounded when the ignition is turned on.



There are a couple dozen different possibilities if you think about a used one. Wrong unit won't work right.