I have a 92 Accord. My turn signals work, but the marker lights (bumper lights) don't. The passenger side marker light stays lit constantly, even with the ignition and blinkers off (it only turns off if I disconnect the battery). The drivers side marker never turns on. Both sides have a constant 12 volts (so it's weird that the drivers side won't turn on. The wiring diagram shows a ground wire that attaches to a ground strip(?; not sure what you'd call it) where several other properly working components are grounded, and a power wire that goes to the ICU. Since that's all there is to the diagram, I replaced the ICU at $175 only to find out that's not my problem. Does anyone know which wire sends the signal to the ICU? Perhaps my problem is in that wire. Thought it might be the flasher unit, but as I said the turn signals work properly. As usual with lighting issues, the turn signals blink fast, while the hazards blink at normal speed. All bulbs are brand new. Thanks for the help.

 

Look under the dash for an aftermarket security system or old wiring. All security systems tap into the parking lights.

 

I do have an alarm. It was put in a couple years ago. It's all pretty new.

 

If the side markers work the same on a 92 Accord as on other Honda/Acura, blink on for signal lights and hazard lights, turn on for park lights, [running lights] and blink off for for signal/hazard lights if the park lights are on and, as you mention, are controlled by the ICU it can really only be the ICU, or the pass. side-marker is getting power [12V+ constant] from someplace else.

Not sure what "back-feeding" 12V+ into the ICU will do to it, maybe keep it from working the side-markers properly.

I would de-pin the pass. side-marker lead from the ICU and see if the side-marker stays on, if it does, problem is is not the ICU, at that point I would check to see if the drivers side side-marker is now working properly, [pass. side disconnected at ICU].

If it is, find short in pass. side power lead, [someplace between ICU and side-marker] before reconnecting, a bypass jumper lead could be installed so you have a working side-marker until you can find the "short".

If the light is out, then it must be the ICU that is supplying the 12V+.

Your 100% sure you did not reinstall the old ICU by mistake?
ICUs are a problem on older Honda/Acura, but for you to replace one with one that has the same exact problem is unlikely.

As far as I know, [do not have a wire schematic for a 92 Accord] the signal into the ICU for the side-markers are just parallels off the park light circuit and the signal/hazard lights circuit, with that wiring diode isolated from the ICU, [ICU can not back-feed 12V+ into park and signal/hazard lights wiring] so the other signal lights on the pass. side would not be on, and that points back at the ICU. 94

 

Thanks for the reply fcm. The marker lights on this car do not turn on with the parking lights, only with the turn signal. I depinned the passenger side as you suggested. Now neither side has any voltage. I also confirmed that I have the new ICU in there. WTF? Here are the relevant diagrams



This is the diagram for the ICU/dash fuse box

 

I connected jumper wires from the ICU to both lights. Still no voltage.

 

I also connected jumpers for ground. Still no voltage. So...once I connected jumpers from the ICU to the lights, I no longer have constant voltage going to the lights, but the lights still don't work. Any ideas?

 

I tested the ground...and from the battery to the light harness (no bulb), there is about 1 ohm of resistance on each side. With the bulbs in, the passenger side light has about 13 ohms of resistance, and the driver side has 50-60 ohms of resistance. I know that the resistance will go up after I put the bulbs in, but why would each side be different? I also threw in second bulb on the drivers side and got the same value. Any ideas?

 

So we are talking about the amber lights mounted in the bumper clip, [signal/hazard only] and not the front side markers, [next to head lights], is that correct?

If so, how do the side markers work, are they both park and signal/hazard lights?
It looks like there would be two bulbs in the front side markers, [one for park lights and one for signal/hazard lights] is that correct?

Have you checked those multi-grounds that the bulb ground goes to?
Disconnect, clean contact surfaces, reconnect.

What are you using to test the circuits, a multimeter, 12V test light or a LED test light? 94

 

They are only signal and hazard lights, not parking lights. I'm using a multimeter. That's how I got the values in my last post.

 

bump