Welcome Guest [Log In] [Register]
Posted ImageWelcome to the all new Geo Metro Forum. We hope you enjoy your visit.

You're currently viewing our forum as a guest. This means you are limited to certain areas of the board and there are features you can't use and images you can't see. Registration is simple, fast, and completely free. If you're already a member please log in to your account to access all of our features:

Join our community!




Username:   Password:
Add Reply
Need wiring diagram for an '85 Chevy C30 Siverado truck
Topic Started: May 19 2012, 06:06 PM (3,026 Views)
JellyBeanDriver
Member Avatar


Need a wiring diagram for a 1985 Chevy C30 Siverado Dually truck. Need how the headlights are wired up from the battery, through the fuse box, to the light switch and lights.

Also want to know how the trailer jack is wired up.

My horseback riding teacher's truck she uses to tow horses with, the head and parking lights went out on her last trip. The shop she took it to tried to fix it (some burned wiring under the dash, and a burned hole in the fusebox where the tail lamp fuse used to be), but they're still out.

The shop bypassed that fuse using an external fused jumper but still no lights.

Figured I'd help her out but would like to know what the factory wiring setup is supposed to be instead of just poking around.


TIA,
Dave
Offline Profile Quote Post Goto Top
 
KKami361
Member Avatar
Elite Member
[ *  *  *  *  * ]
Try This

in before RK :lol
Offline Profile Quote Post Goto Top
 
JellyBeanDriver
Member Avatar


WOW! Very helpful! Thanks!
Someone has been in this truck before OR Chevy wires things differently than other vehicles I've worked on. The battery + cable is wired to the starter and to the alternator output and that's it. From the starter + bolt it goes off to the fuse panel. I've never seen it done this way before.

Autozone eh? Will have to look around their site and see if it has the wiring for the light switch too.
Offline Profile Quote Post Goto Top
 
JellyBeanDriver
Member Avatar


Summary - bad fusible link at the starter lug. I think it vibrated/corroded over the years and one of the wires broke off at the crimp so one of the two large feeds going to the fuse box was dead - the one powering the parking and headlights.

The most useful tool I used for diagnosis was a cheap 3M test light from Walmart, the tip of which was sharp for piercing wire insulation to see if they're live. No need to look away from the wire at my DMM to see what the reading is.

Spliced it back together to confirm it works but am looking up fusible wire on the net to fix it the right way now.
Edited by JellyBeanDriver, May 20 2012, 11:06 PM.
Offline Profile Quote Post Goto Top
 
me and my metro


When I built my 84 Gmc I moved all the hot wires to the firewall and protected the circuits with breakers. The hot lead from the batt is well protected on the way to the post where everything splits up.
Edited by me and my metro, May 20 2012, 11:11 PM.
Offline Profile Quote Post Goto Top
 
JellyBeanDriver
Member Avatar


me and my metro
May 20 2012, 11:10 PM
When I built my 84 Gmc I moved all the hot wires to the firewall and protected the circuits with breakers. The hot lead from the batt is well protected on the way to the post where everything splits up.
It did seem odd to me when I first looked at it that:
- the alternator output went right to the batt
- the heavy cable from the batt goes to the starter and from the starter it goes back up to the fuse box on the inside of the truck.

All my imports and domestic cars, the fusebox comes off the battery terminal, not the starter.

I was sure that the wiring was hacked, but I guess it's stock for a Chevy truck of this vintage.
Offline Profile Quote Post Goto Top
 
me and my metro


Yes they were a real pain to work on, that's why I moved mine.
Offline Profile Quote Post Goto Top
 
metroschultz
Member Avatar
Please just call me; "Schultz"

JellyBeanDriver
May 20 2012, 11:34 PM
I was sure that the wiring was hacked, but I guess it's stock for a Chevy truck of this vintage.
Stock for any GM product of that vintage.
It wasn't till the mid 90's that they began running from the battery to the fuse box, like all the rest of the cars in the world.
Offline Profile Quote Post Goto Top
 
JellyBeanDriver
Member Avatar


Now I'm cornfused as to what fusible link to replace it with.

There are 3 heavy red wires heading towards the battery post on the starter solenoid. Two of them 'Y' together into a fusible link, the black plastic barrel where they 'Y' together has a marking of '16' on it. 16 ga fusible link? I would think so though it's a bit on the light side for 2 such wires.

The other heavy red wire, as beefy as the other two, too goes into a fusible link and that black plastic barrel is marked with a '4'

?! It's certainly not a 4 ga fusible link.

Online what I'm finding is 'GM' starter fusible links of both 14ga and 16ga with a 3/8" ring terminal.

So is the '16' really 16ga? and WTH is the '4' all about?
Offline Profile Quote Post Goto Top
 
JellyBeanDriver
Member Avatar


Tomorrow I'm working on the truck while my daughter's taking her riding lessons. Have 14 and 16 ga fusible wire on a spool, some crimp terminals, solder and heat shrink.

BTW, going to start another thread asking about trailer wiring. I think there's some cleaning up to do here too.
Offline Profile Quote Post Goto Top
 
JellyBeanDriver
Member Avatar


- bought both 14 and 16ga fusible wire on a spool from RockAuto.
- the plastic barrel marked '4' is really marked '14', the '1' is so close to the step in the molding that it's hard to see.
- Cut and removed both existing fusible links, crimped, soldered, heat shrunk in new fusible link of the same length and same original ga.
- the line with the 2 red wires coming together and then going to one fusible link, the 2nd red wire goes right to the alternator field/sense connector so it must be used for voltage sensing. The other heavy red wire goes back to the fuse box and powers the headlight and parking lights.

In other news, it took me forever to find ring terminals that I liked and still I'm not happy. Needed 3/8" ring terminals and the only ones I could find, the O.D. of the ring wasn't much larger than the I.D.

Mouser does sell factory delphi ring terminals HERE the nice ones with plenty of meat and a 2 stage crimp section (one for wire, one for insulation) but I didn't have enough time to get them on order.
Edited by JellyBeanDriver, May 26 2012, 06:47 PM.
Offline Profile Quote Post Goto Top
 
1 user reading this topic (1 Guest and 0 Anonymous)
« Previous Topic · The Geo Metro Lounge · Next Topic »
Add Reply