Well, Ive decided to pay the insurance again, and keep on working on the GTA, trying to fix an electrical problem. What I just found freaked me out. I had taken off the passenger side trim panel, in my struggle to remove the dashboard to check for pinched wires, and found a 3-wire connector just hanging there. So I plugged it into an empty 3-wire connector slot, and it snapped right in. (Of course, I can't get it back out now).

The connector slot is right under the trim plate. There is a silver box on the left, then to the right of that there's a black box with "AC" on it, then to the right of the black box there are the two 3-wire connectors which accept two 3-wire plug-ins. I plugged the 3-wire connector into the top slot, since the bottom slot was already occupied.

The wires attached to this connector are white, green, and grey. Should I leave them plugged in, or should I unplug them again?. The car was running OK until a fuse link blew. I don't think this has anything to do with the fuse link, though.


ANyone know what this connector is for ? Why would it be unplugged ?


I had a mech track down a problem about 2 years ago, and he replaced the computer and prom. Maybe he unplugged it for some reason ???


Thanks

 

white = dome light circuit
grey = dash light circuit
green = a number of things; there are at least 2 shades of green in common use under the dash (light & dark), maybe more; light green = bright lights, and also electric antenna, and some other stuff such as speakers

Does any of this have to do with the ECM? Or is it all body wiring? You can tell by noting which harness it's in. There's one main dash harness, that goes from the big bulkhead connector to the ignition switch, steering column, headlight switch, etc. with a few pigtails to feed stuff like the radio, the instr panel, power to the A/C, batt & ignition to the 2 terminal strips above the parking brake release handle, and a few other small breakouts; there's the A/C harness, that has one pigtail that plugs into the above, and goes through the firewall to the various parts of that system. Then there's the ECM harness, tha tcomes in from the pass side; its only connections to the rest of the car are for ignition, the Check Engine light, the A/C command wire, and a couple of others.

Does this help you figure out what it is?

On your other post, the "knee bolster" is also known as the "hush panel"; the "bracket" is the strip of metal just behind the very bottom edge of the dash that goes all the way from one side of the car to the other. There are numerous small (#8) sheet-metal screws all the way across the bottom of the dash that end up holding the dash to the bracket, and one large machine screw at each end of that, that is the main hardware to hold the dash in. There's a couple of sheet-metal screws above the steering column also, that hold tabs off the back of the dash, and will need to come out.

 

Thanks, RB. I think they are body wiring, since they go off into a corner and disappear. I wonder why everythig was working (as far as I know) with this connector hanging out. Like I said, I can't get it out again, so I guess I'm going to have to hope it is harmless....

On another front...You mentioned chafed wires behind the dash. Guess what, I was poking around down around the left side under the dash, near the hood latch lever and when I pushed a bunch of taped wires up, I heard them rub against the bracket there and make a crunching, scraping sound like metal (wire) on metal (bracket) !

It's too awkward to get a good look at it, but I can feel the edge of the bracket and it's very rough where it rubs the taped up wires, worse than a nail file, so it probably has vibrated right through the plastic and into the wire. There's a lot of wires taped up, about an inch and a half thick, so maybe it was a loom before someone removed that plastic tube that looms have.

woo hoo ! something to fix finally ! I have my hopes up. That's why I want to get the dash out, so I can get a look at this wire, and then just tape it up, or replace it, if possible.

I'm going out to the car now to look for those screws in the dash.

GTA88

 

I guess you can see why this sort of thing is so hard to "take to the mechanic" and expect to get fixed economically.... there's just no "magic bullet" for fixing it, no substitute for taking the whole freaking car apart and looking at stuff until you spot it, hopefully with clues from what fuse blows or whatever.... very labor- and time-intensive, therefore $$$$$-intensive at the shop....

"Body wiring" as such is all at the driver's side, to the left of the clutch pedal location, at the very bottom of the firewall. There's one plug there called the "Fisher body plug" that connects to the tail lights, fuel tank, etc. etc. etc. I'd suspect your mystery plug has something to do with electric antennas actually.

 

That makes sense, since I don't have an electic antenna, therefore the plug isn't needed.

Well, I got a closer look at the chafed wire (s), over on the other side, by the hood release, without taking the dash off. I just pulled the big tube of wires down, gently, as far it would go, so I could get a flashlight on it and a magnifying glass. I peeled back the electrical tape, which was already melted off some, anyway, and what I found was very ugly.
The sharp frame piece had rubbed through 5 different wires, all next to each other, different colors. Some of them just had the plastic insulation rubbed off, and the stuff between the copper and the plastic was showing, but 2 orange wires actually had copper strands showing, and spread out somewhat. There was charring around the exposed copper.

Unbelievable. I guess when I had the car up and down on the jack so much when I was doing the brakes last month, this loom was rubbing itself against the frame. Up, down, up, down, left, right....

Holy cow.... I suppose the short could have fried some electrical parts, too.

***, I suppose I could somehow rewire the screwed up wires, and see what happens. Or replace the whole loom, but what a pain.

What do you think a mech would want, to rewire the burned wires in that loom ? A couple hundred ? It's awkward. He might want to remove the dashboard. I have most of the stuff off already, though.

Still a having a b*tch of a time trying to get the dashboard out, Looks like there are 2 screws behind the radio holding it too.


GTA88

 

How much length of the wires is damaged?

What I would do, if it's reasonable (not more than a couple of inches of wacked wires) is cut them one at a time, slide a piece of heat-shrink over one end and slide it as far away from the end as I could; crimp a non-insulated butt splice onto the ends; and solder it, with electrical solder such as one might get at Radio Shack, NOT plumbing stuff; and put the heat shrink over the entire exposed metal. Then, wrap it about 3 or 4 thicknesses deep in black plastic tape, then put a piece of split loom stuff over that, to protect it in the future. I would suggest putting either a bead of silicone or several thicknesses of tape over the edge of the offending metal.

Once you figure out where all the dash hardware is, you'll see that it's actually pretty easy to remove the dash, with the harness intact and still attached to it; you can unplug it from things like the steering column to let it come out away from them; disconnect the bulkhead connectors fromt he under-hood side (requires loosening one 7mm screw in the middle of them), and then there are 2 screws that hold the fuse box to the firewall; the fuse box will come out with the dash and harness, all in one piece. That should give you enough room to see everything and work on it. You shouldn't have to take everything all the way out if you don't want to, although once you see how easy it really is, you might decide to.

Burnt wires may need to be replaced, if they're so melted that they are bare, or if they've melted significantly through other wires in the harness. If you decide to do that, just cut them off near their plugs or whatever at the ends, and splice in a new piece of similar or slightly larger wire from the parts store using the same technique as outlined above. If they're really ,elted together good, don't try to pull them out, you'll just end up damaging other wires. Then cover the whole thing back up with black tape and/or split loom.

 

Another thing I've done with success is to split a section of vacuum hose lengthwise, and use the hose to line the edge of the metal and bush the wires. Panduit and Thomas & Betts make plastic bushing material for just such a purpose, but it isn't worth buying a whole pack for a 6" section.

 

As far as your wires that were disconnected, I was curious if your car had the performance sound option w/ the 4X6 and the 5.25's in the back instead of the 6X9's. I think that the factory amp for cars with that setup is up in that area, but dont know what wires they use.

Ben

 

I have 2 speakers in the dash and 2 in the doors. The dash speakers look like 4 x 6 's.

 

Wow, thanks for all the info.
OK, I looked at the wires again, and I'm getting encouraged to keep at it. It would make a big difference if I could ge t the loom to disconnect fronm the firewall, so I could move it towards me. Is the bulkhead connector a "snap-in" connector, like the ECM connection ? There is a black box on the driver's side firewall in the upper left of the foot area. Is that the bulkhead connector? The loom goes into the left side of this black plastic box.

On the engine side, approximately in the location of the black box, there is a silver screw sticking out through the firewall, near the maf burnoff relay, with a nut on it. Should I remove this nut to loosen up the black box?

Man, I'm learning a lot about car wiring these days.

 

The bulkhead connector is that great big one to the left of the driver's feet, behind the fuse box, that all the wires go through the firewall in.

On the engine compartment side, it has 2 harnesses that plug into it; one goes to the engine, and has all the non-computer stuff like gauge wires and ignition and all that, and the other has the front cap stuff like headlights, horn, etc. in it. In between those 2 is the screw in question. I think what you're describing is right. Loosen that screw, and the 2 plugs will unplug, together; then on the inside of the car, the fuse box unclips from off of the bulkhead connector, and there's 2 screws in corners of that, that hold it to the firewall.

The way they built the car in the factory, was they assembled the whole dash, with the headlight switch, inst cluster, etc. all in it; then they put the wiring harness on it, and tested it; then as the car rolled down the production line, they stuck the dash in, with the wiring already attached; and plugged in those few connectors that hook it to the rest of the car. They did not do it like most amateur mechanics would try to do it; namely, leave the wiring in place and remove the dash, and then when they put the dash back in, try to plug everything back in from behind. It's alot easier to follow in the factory's tracks and do what you have to do in the same order that they did it.

Once you get over the intmidation factor of this big gob of wires, it's really not that hard at all. Don't let that scare you. Car electrical systems are really simple. Sometime I'll have to show you what a really big glob of wires looks like, from my days as the engineer designing telephone central offices and the switching equipment in them. Think about that for a minute.... if your phone number starts with, say, 678, then there are 9,999 other phone lines whose number starts with 678; and if in your neighborhood there are also people whose phone #s start with 676, 677, and 679, and maybe 332, 334, 335, 336, and 338, then there's 10,000 phone numbers in each of those groups too; that's 90,000 phone numbers right there, each of which has 2 wires, and they all terminate on one giant "connector", namely a group of terminal blocks. Then there are far more wires than that within the CO, interconnecting all of those to the switch gear, and leading toward the outside world (other COs - something you don't have to worry about in a car). For the last couple of decades I've been a broadcast engineer, building radio and television stations. Those are alot simpler than COs, but still make a car's wiring look like a desk lamp's by comparison.

 

Wow. Thank goodness for optical concentrators and fibre...

 

i know exactly what you're talking about, rb..... i used to work for a local internet service provider 2 years ago. one of the big projects we did was wire a local resort for dsl internet access. it was a pita due to having to trace the wiring from all the rooms into the equipment room. then we'd have to test each room's connection, and re-do wires if need-be. then we wired up our own board, looks like a connection board for telco usage. what we did next was tie blocks of rooms together into groups then ran them to the switches (network equipment) fun stuff that job was.