Let's talk wiring in the dash
12-02-2016, 12:25 AM
#1
Melting Slicks
Thread Starter
Let's talk wiring in the dash
So I am working on a 1984 C4 that has been sitting outside for 4 years with the passenger side window rolled down. Needless to say there was a lot of varmint activity in the car.
Electrically speaking, nothing works.. My idea is to change the harness that runs through the dash instead of trying to repair what's there. What is your opinion?
Also, does anyone happen to know the hours GM would call for to replace the dash and harness?
Electrically speaking, nothing works.. My idea is to change the harness that runs through the dash instead of trying to repair what's there. What is your opinion?
Also, does anyone happen to know the hours GM would call for to replace the dash and harness?
12-02-2016, 05:30 AM
#3
I bet it wouldn't be that bad once you got the dash off.
In my limited experience with these it is about space. Things are in layers. Uncovering and working on them isn't anymore complicated than a pickup it just takes more time.
I would just get it running first. I'm not sure I would tear into the dash. I know I wouldn't.
Change the oil and gas. Put a battery in it and see what happens.
In my limited experience with these it is about space. Things are in layers. Uncovering and working on them isn't anymore complicated than a pickup it just takes more time.
I would just get it running first. I'm not sure I would tear into the dash. I know I wouldn't.
Change the oil and gas. Put a battery in it and see what happens.
Last edited by Lazy Tom; 12-02-2016 at 05:35 AM.
12-02-2016, 11:04 AM
#4
Melting Slicks
Thread Starter
I bet it wouldn't be that bad once you got the dash off.
In my limited experience with these it is about space. Things are in layers. Uncovering and working on them isn't anymore complicated than a pickup it just takes more time.
I would just get it running first. I'm not sure I would tear into the dash. I know I wouldn't.
Change the oil and gas. Put a battery in it and see what happens.
In my limited experience with these it is about space. Things are in layers. Uncovering and working on them isn't anymore complicated than a pickup it just takes more time.
I would just get it running first. I'm not sure I would tear into the dash. I know I wouldn't.
Change the oil and gas. Put a battery in it and see what happens.
12-02-2016, 11:15 AM
#5
Zen Vet Master Level VII
12-02-2016, 02:01 PM
#6
Safety Car
Electrically speaking nothing works....
Hello Blue Bomber,
I have a 1988 Coupe that sat for several years under a cover but somehow it developed a lot of corrosion related electrical issues. I found the most of the big issues were related to my fuse block. I checked the fuses and they all "looked" fine but yet nothing got power. I checked the fuses with a Volt Ohm meter and there was no continuity on most of my "good fuses".
I bought some new fuses and before installing them I cleaned the contact surfaces on the fuse block. After installing new fuses my electrical system came back to life.
Go to the post (if your year has one) behind the battery where the 12 volt Positive connects to the rest of the harness and be sure to clean it and the connectors really well. On my '88 there are several fusible links that get their power at this point so be sure that you have full battery voltage at the post.
Clean the electrical ground straps and verify that you have full battery voltage using the engine as a "ground". Be sure that the engine is grounded well as that can introduce many problems with the fuel injection system. You should check for voltage drop as you go further into the car. I found several connections where there was corrosion had caused faulty readings on engine sensors and some made voltage drops of over four volts.
I removed my digital dashboard and cleaned it's connectors and pins thoroughly. I replaced all the light bulbs in there while I was at it.
Now I have a car which starts up, runs, and the dashboard and radio work and life is good again.
I have a 1988 Coupe that sat for several years under a cover but somehow it developed a lot of corrosion related electrical issues. I found the most of the big issues were related to my fuse block. I checked the fuses and they all "looked" fine but yet nothing got power. I checked the fuses with a Volt Ohm meter and there was no continuity on most of my "good fuses".
I bought some new fuses and before installing them I cleaned the contact surfaces on the fuse block. After installing new fuses my electrical system came back to life.
Go to the post (if your year has one) behind the battery where the 12 volt Positive connects to the rest of the harness and be sure to clean it and the connectors really well. On my '88 there are several fusible links that get their power at this point so be sure that you have full battery voltage at the post.
Clean the electrical ground straps and verify that you have full battery voltage using the engine as a "ground". Be sure that the engine is grounded well as that can introduce many problems with the fuel injection system. You should check for voltage drop as you go further into the car. I found several connections where there was corrosion had caused faulty readings on engine sensors and some made voltage drops of over four volts.
I removed my digital dashboard and cleaned it's connectors and pins thoroughly. I replaced all the light bulbs in there while I was at it.
Now I have a car which starts up, runs, and the dashboard and radio work and life is good again.
Last edited by ctmccloskey; 12-02-2016 at 04:22 PM. Reason: word change
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95BlueBomber (12-05-2016)
12-03-2016, 06:02 PM
#7
Race Director
Not knowing what circuit or circuits are messed up...it is hard to advise you on what to do.Repairing a bad cirucit(s) in some cases is easier then going through what it takes take this dash out....because I have done it. it is not impossible...but like it had been mentioned...it is 'layered'.
And I have not seen nor looked to see if new harnesses for your car are being made. So actually finding a good used one that is worthy of the effort...is questionable.
If you want a time 'quess-timate' from someone like me who has done it. Assuming that the car is still correct in all ways...it would easily take me at least 20+ hours to go down and back up with it...and that is also time to correct any connections I find inferior. Figure in added time for aged fasteners and things breaking or previously broken...you can add to that.
DUB
12-05-2016, 04:04 AM
#8
Race Director
It would be nearly impossible to get an accurate guesstimate because no one short of a specialized rebuilder would consider replacing the main harness. It's possible a dealership MIGHT consider it on a problematic newer car still under warranty, but that might end up resulting in the car being returned to a factory (lemon law?).
I've had LOTS of my dash apart over the years and wouldn't be excited with the prospect. I'd probably consider parting it out (selling it) before that significant of a rewire. I'd be way more apt to start tracing continuity through existing wire to find the problems.
Part of the main harness goes through the firewall/dash while other parts run behind the engine down to the transmission. To replace the whole thing, I think you'd have to be down to the chassis for it to make any sense.
Start at the fuse block as suggested. Don't even consider working on one of these (electrically) w/o a FSM.
Now that I think about it, JrRifleCoach's reply was more succinct: YIKES!
I've had LOTS of my dash apart over the years and wouldn't be excited with the prospect. I'd probably consider parting it out (selling it) before that significant of a rewire. I'd be way more apt to start tracing continuity through existing wire to find the problems.
Part of the main harness goes through the firewall/dash while other parts run behind the engine down to the transmission. To replace the whole thing, I think you'd have to be down to the chassis for it to make any sense.
Start at the fuse block as suggested. Don't even consider working on one of these (electrically) w/o a FSM.
Now that I think about it, JrRifleCoach's reply was more succinct: YIKES!
12-05-2016, 05:27 PM
#10
Race Director
Knowing the actual circuit(s) that is/are giving you grief would be helpful.
That way you can be directed to a repair process...instead of getting into it when you really did not need to.
You initial post sated that nothing worked...but later the car was running.
So this is why I am asking on what is not working. Unless you just want to get into it. I have more times than I can count and I know what it takes...and just trying to save you a lot of effort if not needed.
DUB
That way you can be directed to a repair process...instead of getting into it when you really did not need to.
You initial post sated that nothing worked...but later the car was running.
So this is why I am asking on what is not working. Unless you just want to get into it. I have more times than I can count and I know what it takes...and just trying to save you a lot of effort if not needed.
DUB
12-05-2016, 08:12 PM
#11
Melting Slicks
Thread Starter
Knowing the actual circuit(s) that is/are giving you grief would be helpful.
That way you can be directed to a repair process...instead of getting into it when you really did not need to.
You initial post sated that nothing worked...but later the car was running.
So this is why I am asking on what is not working. Unless you just want to get into it. I have more times than I can count and I know what it takes...and just trying to save you a lot of effort if not needed.
DUB
That way you can be directed to a repair process...instead of getting into it when you really did not need to.
You initial post sated that nothing worked...but later the car was running.
So this is why I am asking on what is not working. Unless you just want to get into it. I have more times than I can count and I know what it takes...and just trying to save you a lot of effort if not needed.
DUB
12-06-2016, 06:57 PM
#12
Race Director
If you do not have one...I would be getting a wiring schematic for your 1984. I have the factory Service Manual and it has the wring diagram and how many of the electrical components work in a very good format.
If you do not have a factory Service Manual...you might want to look into getting one. It will be worth the money.. And I do not mean Chiltons, Mitchell. or any other. Get a GM one from any of the major Corvette suppliers like Ecklers, Corvette Central, etc.
DUB