Weird Electrical issue 1990 Suburban 2500 w/7.4

[stevehayes01]

Hey everyone this is my first post here so I want to say thank you in advance for any help you guys might have.

So I just bought my truck yesterday and it seems to have developed a weird electrical issue overnight. The radio, overhead lights, cigarette lighter as well as other accessories in the car work intermittently. If any of the controls like door locks, Horn or anything is used the radio goes off.

I am suspecting a ground wire but just dont know......anyone else ever experience this type of issue?

 

[Fobroader]

Thats a definetly a ground issue, good luck man, grounding issues are usually a ***** to find!!

 

[badazzbulldog]

does it have an aftermarket stereo in it?

 

[BHBurban]

X2 on checking grounds first, but what is your voltage reading at the battery, at idle?

 

[Butch]

X3 on grounding issue, sounds like all those items run through the courtesy fuse as well.

 

[stevehayes01]

does it have an aftermarket stereo in it?

Yes it does.....its got an old Kenwood Cassette deck in it.

 

[stevehayes01]

X2 on checking grounds first, but what is your voltage reading at the battery, at idle?

I am seeing between 12.7-13.0V at idle right now...but not sure on these trucks what standard is. On my other car which is a SAAB it usually runs 13.5 or so at idle so this seemed a little low to me.

 

[badazzbulldog]

check wiring to radio i've seen some hack jobs that people have wired that wreak havoc on wiring to other components in the cab

 

[Mean Green]

Check your cigarette lighter connection, I've had GMT400's in the shop before with the same symptoms (no courtesy features such as the radio, courtesy lights, cigarette lighter). Your problem is a ground issue or possibly a short somewhere. Also your radio issue could very well be unrelated to the rest of the problems, I would reccomend pulling the head unit out and see if the wiring done by the previous owner is up to par!

 

[stevehayes01]

Check your cigarette lighter connection, I've had GMT400's in the shop before with the same symptoms (no courtesy features such as the radio, courtesy lights, cigarette lighter). Your problem is a ground issue or possibly a short somewhere. Also your radio issue could very well be unrelated to the rest of the problems, I would reccomend pulling the head unit out and see if the wiring done by the previous owner is up to par!

Ok cool.. I Will check that. I got side tracked today when the heat shield between the transmission and exhaust decided to lose all of its bolts except one and start making a nasty rattle. So tomorrow onto the tracking down all the leads and grounds.