Weird side-marker problem, no flash... unless the hazards are on... sometimes

hurleyman

So I have a problem... I just can't let her go...

Anyway, the current problem is that the side-marker lights that are supposed to blink, only blink when the hazard lights are on. When the turn signal is selected, they will flash once or twice and then remain either on or off, depending on whether the parking lights are on or off, without flashing. They used to flash more times before they got to this point, but the problem has gradually progressed from several flashes to now just one... and sometimes not even one.

Compounding details:
The parking light switch turns those same lights on and off just fine.
The same lights flash just fine when the hazard lights are turned on.
The signals in the front bumper, and the rear signals all work just fine, regardless of what the side-marker signals are doing.
I replaced the "side-marker control relay" last week.
I replaced the turn-signal relay recently.
I've done LOTS of screwing around with the wiring, and had to wire in some new switches to bypass the partially broken multi-function switch (so I could have fried something in the midst of said screwing around).
The screwing around was BEFORE I replaced the relays, so any problems caused by the screwing around shouldn't have affected the relays.

AAAAAND I can't find a decent wiring diagram for the lights!

What else could be wrong? Thanks!

hurleyman

Correction... The side-markers flash just fine if the parking lights are off. When I turn the parking lights on, they'll flash a time or two and then just stay on.

greenteagod

Yeah sounds like a wiring issue to me, faulty connection somewhere. Based on what you've described it seems like they're not getting enough power. I'd suspect a relay but you said you've replaced those. I'll take a picture from my service manual of the wiring diagram, when I get home, if you don't find anything before then.

hurleyman

That'd be great! I have a Chilton's manual, but it's for the CRX, Civic, Wagovan, and del Sol... and anything else that's remotely similar. So, it has a whole bunch of wiring diagrams, but the ones for the Wagovan don't include the lights! And the ones that DO include the lights don't match my car! That makes it hard to know if I've looked at all the relays/controllers involved.

So, it seems like the flasher/relay can't be broken because they DO flash when the hazards are on. It also seems like the controller shouldn't be bad because it's new, though I wouldn't entirely rule that out. SO, my inclination is that there's some controller that dictates how and whether the side-marker flashes. They flash in sych with the bumper light if the parking lights are on, but they alternates from the bumper light if the parking lights are on...so something makes it do that. Whatever that is, it's the only thing I haven't found and screwed with or replaced yet.

Thanks...

jpciii

Your problem likely lies in the Integrated Control Unit. It's a little brain-box of sorts that controls some lighting and wiper functions among other things. It's about the size of a cigarette pack and is plugged into the back side of the under-dash fuse box. I suspect the solder joints have cracks (same problem as the extremely common main-relay issue). Re-flow the solder on the pins through the circuit board, and hopefully, you'll be good to go.

Also, I think you will find that a real factory service manual for your car is VERY useful.

hurleyman

:-/ Looks like that was it....

Anybody have a known-good ICU I can buy...for less than the car's worth?

Haydz

Like jpciii said, you can start by reflowing any solder on the PCB. If that fails then look to replace the unit.

greenteagod

Yes, definitely reflow solder first, it's pretty easy to do. Pop it open take a look at the contacts if there is any separation just reflow those spots. Hell if you're near Austin I'll do it for you for a bottle of Dr. Pepper.