Weird Issue

walkerbe

Daily Driver
Sep 22, 2013
30
0
0
I recently took the dash and column out of my 78 Malibu to put in a better dash and tilt floor shift column. After getting the new dash in and a wiring hooked up I realized my turn signals and brake lights wasn't working, which they worked before. I tried changing the flashers to no avail, I tried grounding the wiring harness better and the problem persisted. The only thing that I have noticed is that the turn signals will work when the cluster and light switch is out, but when the light switch is in and headlights on they will not work. The same applies to the fan, if the light switch is out the fan runs as expected but when you plug the light switch in there is a noticeable difference and when the headlights are turned on the fan essentially bogs down to the point it's not running at all. It seems as though when the headlights are on the nothing beyond that point along the wiring harness will work correctly. And I have tried multiple switches so I'm assuming it is not a bad switch. I am at a loss as to what might be causing the issue or what to try next. Any help would be greatly appreciated!

Thanks and God Bless
 

walkerbe

Daily Driver
Thread starter
Sep 22, 2013
30
0
0
I can't see any wires that may be pinched. One thing I did notice is that I missed maybe two staples before putting the harness back in and one hit something metal causing an arc. I know a fuse was blown but wonder if its possible a wire was burnt behind the staple causing a short. The only thing I wonder is if a short in a wire near the cluster would cause the issue of things losing power once I turn the lights on?
 

t01blaze

Amateur Racer
Dec 14, 2011
247
0
0
South New Jersey
walkerbe said:
I tried grounding the wiring harness better and the problem persisted.

I was going to suggest a ground issue. I've seen it a few times. Are all the grounds in the factory locations?

I had an '84 Z28 years ago and the radio was missing and the plug was cut off. I identified all the wires but I couldn't find the ground wire for the radio. I made my own ground wire and grounded to a dash mounting screw under the dash. Everything was great until I turned the headlights on. The radio shut off. I turned the headlights off and the radio came back on again, but I lost the clock and radio presets. :-k Took me a while to figure out it was a bad ground. I moved the ground wire to a better location and it solved the problem for good.

I also once had a problem where someone installed a trailer brake controller and grounded it under the dash, just like the wire had a tag that says not to. Grounded the trailer brake controller better and the trailer brakes stopped pulsing and buzzing and worked like their supposed to.
 

walkerbe

Daily Driver
Thread starter
Sep 22, 2013
30
0
0
The three grounds I have checked is the one from the negative battery wire to the fender, the wire that mounts to the alternator bracket and the thick wire that comes off of the harness to the bottom left of the dash where it bolts to the frame. Is there any grounds I may be missing? Does the main harness have just one thick ground wire?
 

walkerbe

Daily Driver
Thread starter
Sep 22, 2013
30
0
0
Tonight I noticed a small ground wire that mounts in the same position as the thick ground wire that comes off of the harness and mounts to the frame behind the e brake release. The wire has broke at the mounting tab on the bolt that bolts the dash in. I looked at the diagrams but can't tell what that smaller wire grounds, any insight?
 

t5montecarlo

MalibuRacing Junkie
Oct 21, 2007
4,632
31
48
Lederach, PA
garage-scene.com
If the dash is not grounded to the body and you are relying on grounds to the dash, you have found your problem. The electricity is finding a different path to ground, via other circuits, and causing the issues you are experiencing, just like t01blaze described.
 

walkerbe

Daily Driver
Thread starter
Sep 22, 2013
30
0
0
I imagine that is my issue. The large wire is grounded to the frame good, but the small wire is broke now the issue becomes figuring out where the broke wire is at or what it goes to. I hope to look at my brothers Monte tomorrow to see if I can figure it out. Thanks for the help, if anybody has any insight into the smaller ground wire please let me know. Thanks again
 

Doober

Moderator
Jun 2, 2003
14,704
1
38
Catalina, AZ
www.cardomain.com
I don't think it will make a difference, but there is also typically a braided ground strap that runs from the engine (usually an accessory bolt hole on the head) to the firewall. I believe there is a ground wire near the end of the dash at the bottom on one side or the other, but i may be thinking of a different vehicle.
 

walkerbe

Daily Driver
Thread starter
Sep 22, 2013
30
0
0
Now that you mention it I think I do remember the ground wire from the head. And yes there is at least one ground wire on the left side of the dash near the e brake, I'm thinking there may be a second one that has been broke in my Bu which could be my issue.
 

MalibuRacing.com Gear

Stickers & Shirts!!