i have a 93 civic cx hatchback im that working on and since i bought it there has been a problem with my turn signals and interior lights. The signals are really messed up, if i turn the left signals on, the back lights all flash on both sides. The front ones stay on solid i think if you turn on left signal, and the interior lights like in my gauge cluster and my heat and cooling controls are all dark when the lights are on.
If anyone could give some input on what the problem could be i would really appreciate it. Thanks.

 

Check your grounds, when one circuit, [signal lights] have an effect on another circuit, [dash lights/park lights] it is almost always a grounding issue, check the tail light ground(s).

Check the tail light bulbs, make sure they are the correct ones.

Unplug the tail lights and see if you still have a problem, [front signal lights and dash lights]. 94

 

i unplugged the tail lights and there still wasnt any difference, im having trouble finding the grounds, do you know where they are on my car or is there a diagram somewhere that shows?

 

Should be grounded around trunk/hatch latch, [behind trim]. 94

 

i found that one and i sanded underneath it and it didnt do anything

 

Then something is miswired or shorting out, would be my guess.

Do the hazard lights work properly and without affecting the dash lights?

Try unplugging the rear harness at the under dash fuse box and try the signal lights and dash lights again. 94

 

i unplugged the rear harness and it still did the same thing i turned the key on turned on the lights and there was still no gauge cluster lights ect., so do you think it is miswired?

 

It tells me the problem is not in the back, [tail lights, bulbs, wiring harness or grounds, meaning the problem is in the front of the car.

Do the hazard lights work?
Do the park/running lights work?
Do the head lights work?
Do the high beams work?
Does the flash to pass work?
Have you rechecked the fuses?
Have you made sure all harness plugs are plugged in properly?
Does the car have an alarm or remote start, or any other aftermarket electronic device added?

After the signal light switch the left and right side signal/hazard lights wiring are compleatly separate circuits, except where they go to the ECU, [that controls the front side markers] try unplugging the ECU and see if it makes a diff.

Do you have or can you borrow a multimeter?94

 

Hazard lights work prefectly.

Running lights don't, when you turn them on the right side turn signals stay on solid without blinking and right indicator light stays on solid in the cluster.

Head lights work, but same thing happens with the turn signal like above.

High beams work but same thing as above.

Driver side turn signals work fine

Passenger side turn signals, both front corner lights blink, rear looks like you have the hazard lights on, like all the stuff on the back lights up except for the driver turn signal light

all fuses are good

last night i tried to make sure they all were plugged into the fuse box properly

the only after market electrical device is a different sterio, but the problem was there before i put that in

i'll try unplugging the ecu in a little bit and tell you what happens

yea i can barrow a multimeter i think

 

Not the ECU, the ICU, [Integrated Control Unit], should be mounted to the back of the under dash fuse box, among other things it controls the front side markers, flashes them on for signal lights and hazard lights, turns them on for park/running lights, flashes them off for signal and hazard lights if the park/head lights are on, it is the one common factor between the park/running light circuit and the signal/hazard light circuit and the left and right side signal/hazard lights circuit.
Anything else not work, door/seat belt/key in ign. chimes, rear window defog, also controled by the ICU, problems with the ICU are common on older Honda/Acura. 94

 

oh ok haha i was wondering why i was pulling plugs out of the ecu. All those things work, i'll try unplugging it and let you know what happens

 

i unplugged a bunch of them on the back of the fuse box and kept trying the lights and one made all the front lights turn off, but no difference inside, would you know what color the plug would be?

 

ok never mind i found out what it was. i pulled it away from the fuse box and it didnt make a difference. i also borrowed a multimeter today for whatever i have to do with it