Strange radio/intermittent wiper problem. Any ideas?

[Meantime]

Ok guys, here's a good old electrical problem for you (love these)

For a while now, my intermittent wipers have been...intermittent. Sometimes they work, sometimes they don't. Recently I took the stereo out to hook up some new speakers; when I put it back in, periodically it would shut off and then turn itself back on. I noticed that when it was working, the int. wipers worked; when it didn't, the int. wipers didn't work either.

So a week ago I hit a bump, and all of a sudden both the radio and int. wipers completely lost power. Nor would they magically turn themselves on again. So I started doing some investigating. The int. wipers and radio run off of the same 10 amp fuse in the box, and also have a blue ignition wire running to them from the ignition switch (ACC). Checked the fuse, and it is intact. Then I checked voltage of the blue ignition wire to the radio and TCU - in both places it was only pulling .72 volts through that wire when ignition is turned to ACC. (should be pulling 12 volts). So it looks like the problem is the blue wire. Somehow it is just not getting enough power.

I did some digging around the fuse box and SMJ but it is such a tangled mess of wires that I found it very difficult to trace the blue wire and see if there's a break anywhere. Haven't dug into the steering column yet to test the wire at the ignition switch. So long story short, I have two questions.

1) Would it be possible for me to run a separate ignition wire with its own fuse to the ignition switch (assuming it has power there), just so I can get the radio back on? I can live without the int. wipers but the lack of radio is a real pain. If so, how difficult is it to get to the ignition switch?

2) Besides the SMJ and the fuse box, any other ideas where the blue wire may be shorting out, or any other tests I can run to narrow it down?

I'd rather fix the problem within the factory harness, but if it comes down to having to take the dash off and start cutting through the harness, I'd rather just rig a wire to get the radio to work. Any help is appreciated. Thx...

[s13sr20chris]

ah hah! a jury rigger like myself! dont think of voltage as a pull. voltage is the push. tracing the wire is a good idea. if you can verify the source has power then the wire is messed up. the fact that you have some voltage steers it towards a frayed wire or something. you ca run another wire if you need to. i have done that a few times. just be sure to cut and tape the wire you are no longer using as you dont want to cause a short.

[Meantime]

Thanks - I'll measure the voltage at the ignition switch itself this weekend and see if it is pushing 12V there. If it is, then I'll just run a new wire. The fuse block is too many wires in too small a space and I smacked my head a dozen times trying to get at it yesterday.

Probably a stupid question here, but where's a good place to get a wire with its own fuse attachment? I know I've seen them before, just don't remember where. I'm an electrical noob in case you haven't noticed.

[s13sr20chris]

stereo shops have ggod stuff but its not cheap. you coud prob find a fuse socket with some wire at the auto parts store.

[Meantime]

Update - fixed the problem this weekend. I checked the 10A fuse for the radio and int. wipers and it was getting 12V, so no problems from the ignition switch wire. I unbolted the fuse box and jiggled the wires near the fuse, voila, everything works again. Electrical gremlin has been slain.

[benemorius]

Hey Chris - Do you have any remarks about the wiring in s13 dashes? Mine is all fubar'd. Seatbelt light comes and goes as it pleases. My intermittent wipers only work when the headlights are on, except sometimes when they don't feel like it, in which case I can turn on the rear defroster and they start working. It used to be even worse until I noticed the radio fuse was blown and replaced it. (the radio has always worked, so I hadn't even bothered checking the fuse for the longest time...??)

Anyway... I'm not asking for help on fixing it. I'm just wondering if s13's commonly have issues like this. My friend who owned the car before me said that he paid to have a dealership fix all the dash wiring problems one time, but that different problems turned up shortly after that and he never did anything about it. He says s13's are known for having such problems, but he's had so many different cars in the past few years he frequently gets their histories all mixed up.

[s13sr20chris]

known for it? no, i have yet to see an s13 in my shop for busted up dash wiring. i have seen a few come across this forum though. i will say that the key in your case is tracking down why things work only in conjunction with other things. its that common fault that will ease the headache. either power or ground is being denied to the component in question and it will backfeed throught the other circuit. this can cause wierd problems. i hate messing with dash harnesses just because its behind the dash. yuck.