Rep Power: 0

Having some electrical problems on my 05 Civic LX. This problem is somewhat intermittent but is now pretty much the norm.

Symptoms:
RF low beam does not work.
R turn indicator comes on when headlights turned on. Right turn signals do not function when headlight switch is on. Functions fine when headlight switch is off.
R turn indicator comes on when the A/C switch is pressed on. Right turn signals function but in a slower manner.
Blower motor shuts off when headlight switch is turned on.
Dash brake light comes on when headlights are turned on or the A/C is turned on.

Troubleshooting done:
Battery/Alternator OK
Swapped headlights - problem remained
Swapped headlight relays - problem remained
Checked fuses - good
Check continuity in the headlight / turn signal assy. - all good
Did troubleshooting on the Multiplex Control Unit up to swap the unit out.

Any suggestions before I put down about $240 for a replacement? This is for my son's car and I am out of work right now so I would like to be sure.

Thanks in advance.

 
Rep Power: 307

You have a tough one here for certain. The turn signals are certainly part of the under dash box, BUT I cant see any way they are tied into the multiplex system though. It would be an expensive gamble.

My other thoughts are a poor ground somewhere.

You might try gently moving the connectors feeding in/out of the under dash fuse box and look for changes in the symptoms.

 
Rep Power: 0

CraigW - Thank you for your reply. This has been a tough one. I buttoned everything together today and except for a few brief periods of acting up the car performed fine for the rest of the day. I will pull out the manual and run through the grounding points. Of course if it is not acting up then it is hard to troubleshoot...........