so i have been having an electrical issue on the 84 estate.. while driving if i hit a bump my check engine light would flash and my radio would turn off then back on again. this has been going on for a bout a year. have been having problems finding something that wasnt "broke all of the time". well tonight i was driving in a storm and hit a pot hole, it jarred the car a little not enough to damage anything but it was enough to finish off the flashing problem. i lost headlights, marker lights, horn, radio, clock, dome light,and high on the blower motor. turn back up, brake, hazard, power windows, and idiot lights still come on, and the car starts and charges. any ideas would be great. i do have an idea of what it may be but i dont want to give any ideas out to sway what other ideas might come back in. ....... thank you fellow long roofers.
That's an oddball combination! I would start at the fuse block. If the dead circuits did not blow fuses, I would pull the fuses on the dead circuits and check each circuit for power on the battery side of the fuse. First, check the fusible links at the starter solenoid. One of them supplies power to the A/C, headlights, taillights and courtesy/clock fuses. That link might have a bad connection or it could be blown. It is labeled "Fusible link A" on the 1985 wiring diagram, but I don't know if the link has any visible identification marks on it. If the fusible links are good, I would look for broken or corroded fuse block terminals or a bad buss connector (metal jumper strap that feeds power to several fused circuits) at the bulkhead connector. If the fuses for the dead circuits are blown, then you'll need to look for chafed wires/shorts between the fuse block and the devices. Do you have the Chevrolet Service Manual for the car? The proper wiring diagrams will make this much easier.
I was going to say to check the fusible links first of all. Almost all of the things that are out are always powered.
my guess would be either fused links or maybe a loose conection on a power junction block under the hood if it has one. drive on over to KC and bring it to my house and we will get it fixed but you gotta buy lunch.
my 2 cents id say short, bad ground wire or faulty inline fuseable link, and or possible bare wire shorting when jar the body id start check all fuses if all good, check for a short start by disconnecting neg terminal on battery touch it back to battery look for a spark, sign of short then id hook a test light to neg terminal and to the neg battery cable, light will be on, start pullin fuses till light goes out and that's what wires , harness ya need to follow for frayed wires that are grounding out . also id run a separate ground wire from frame to engine most common problem is lack of good ground.
If the fuses are good, and I would guess they are, because it started out as intermittent, then it is probably a bad ground. I am not sure where your ground for the affected system is, but I would look at the base of the A pillar on the driver's side. My 91 OCC has a couple of grounds there, and I do not think GM made any major changes like moving them. There may be a broken wire, but it would be on the ground side of the system that is failing. If the fuses are good you probably do not have a short, or you would have blown them. The term for a system not working with good fuses and voltage at them is an open to ground, not a short. Shorts blow fuses, and then nothing works in that circuit until the short is fixed. A short would also occur between the fuse and the non working system, drawing more amperage than the circuit is designed for (fuse value).
You have a bad ground somewhere. Possibly a weak ground or not tightened properly. I'd start with the radio connections. Make sure that bad boy is hooked to a solid, heavy ground to the frame of the car. Body of the car is not always sufficient. Also, check the ground at your starter near the fusible link. It may be loose. The ground at the starter is more likely, now that I think about it.
ok so i posted this up a while ago and just thought anyone who gave advice thanks first of all... it was a fusable link at the starter... the one for constant power..
Thanks for your update. It's things like this that may save another member a lot of time. Now while out riding around try to stop hitting potholes.
