CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

For those of you who hate electrical, how would u like to have these problems come up

JDNobodi

3/4 ton status
 Premium
GMOTM Winner
Joined
Oct 9, 2002
Posts
8,488
Reaction score
32,939
Location
Santa Maria, CA
I was planning to write this earlier, but I didn't feel like typing a novel. So here we go.

As some of you may know, I'm fixing a Dodge Cummins which has been in a fire.
https://ck5.com/forums/threads/another-dodge-cummins-in-a-chevy-forum-my-rescued-tow-rig.307345/

After buying a few harnesses from eBay and making those work together.
https://ck5.com/forums/threads/rant...zaki-during-the-nineties.313104/#post-3444869

I plug everything together and hook up the battery and only half the stuff in the cab works.

****
Okay, here is a list of things that don't work.
Instrument cluster,
Rear brake lights,
Turn signals,
Hazard Lights,
Radio,
Blower motor, Hell, it could be the whole HVAC system,
Dome lights,
and most of the buzzers except the seat belt buzzer.

I know some of you treat electricity like it is some creature of the night and you cross your fingers at it screaming "Back thou foul spawn of Satan."

I'm not like that and I some what enjoy making something electrical work, but even this would deflate my sails.

Oh, one thing does work, that is the third brake light, but it is on full time. ****ing great.














I've got some things going, but I write about that later.
 
Last edited:
Thanks, but I already have the factory service manuals and have been studying them.
 
Hmmm, sound like my kind of fun......
I actually enjoy that kind of stuff.

Without seeing any schematics, sounds like you have some kind of dual power feed in the system, and one is missing.

Study that third brake light carefully. It sounds like it might be trying to backfeed all the dead stuff.
 
There is no way. It would be for sale.


Actually id prolly rip the motor out and sell the rest. Put the motor in a cheby
 
Hmmm, sound like my kind of fun......
I actually enjoy that kind of stuff.

Without seeing any schematics, sounds like you have some kind of dual power feed in the system, and one is missing.

Study that third brake light carefully. It sounds like it might be trying to backfeed all the dead stuff.


These things were my first thought also.

I love wiring.
 
check all body to frame/engine grounds.
 
Just so you guys know, I'm taking notes on whole loves wiring and I bet I'm not the only one! lol
 
when I left the one from the fire wall to motor (pass side) off of my old burb I had all kinds of issues. gauges, etc.
 
Just so you guys know, I'm taking notes on whole loves wiring and I bet I'm not the only one! lol

I'm kinda surprised at how many people are saying who like it.
I wanted more haters so those who like wiring could ridicule who don't.
As I've said, I have solved some problems, but have found more problems also.
I just have not had any time to write part two of the novel. Maybe tonight.
 
Last edited:
I wanted more haters so those who like wiring could ridicule who don't.
You can put me down for some ridicule. :D

Of course I'm also rebuilding a wiring harness and fuse/relay panel for my truck and to be honest, it's not as hard as I expected. I'm actually kinda enjoying the process so far. shhhhh
 
With simple power with no logic, trouble shooting is fairly straight forward. Power, ground, switches etc. Only issue I ever have is not one gm vehicle I have owned had the correct color scheme for wires, so you just have to deloom the entire harness and ohm it out.
 
With simple power with no logic, trouble shooting is fairly straight forward. Power, ground, switches etc. Only issue I ever have is not one gm vehicle I have owned had the correct color scheme for wires, so you just have to deloom the entire harness and ohm it out.
I never notice that problem. GM is usually consistent with their wiring codes. In fact, aftermarket harnesses usually follow GM's wiring code. I've found small changes over the years. Such as the ignition feed wire. Tan for points and pink for HEI. Same for the fuel gauge wire. The alternator wires have changed also.
I have found that some times the colors fade over time.
 
Last edited:
Part two of the novel.

When trouble shooting, start with the simple stuff first. As Fordum said, it may be a duel feed system. There was one wire I did not hook up to, so I hooked it up. Nothing.

Okay, let check fuses. I start probing fuses and the hazard light fuse was blown. Replace the fuse and only the front lights and the right turn indicator flashed. That is good and bad. It shows I have connection between the original cab harness and the replacement under hood harness for the front lights. Since the indicator lights are wired to the front lights, It probably means the left indicator bulb is burned out. Going to have tear the dash apart for that one.
The rear lights not flashing is still a concern. The rear tail lights work but are dim, and sometimes the lights stay on when the headlight switch is off. Did the the 97 have that annoying feature that new cars do where the lights stay on for a about a minute?

Blower, radio, and turn signal fuses are good. I'm not sure about about which fuse does the dash though. I checked the book and it suppose to be fuse 12 in the cab. I don't recall there being a fuse there. Checked and yep, no fuse. What does the panel says it suppose to be? It reads
AIRBAG
CLUSTER
Well that makes me feel smarter, because when I looked at it earlier, I thought it was for the "AIRBAG CLUSTER" not "AIRBAG and CLUSTER". DUH.

I put a new fuse in and the dash works. Awesome. The idiots lights that is controlled by the PCM work too. Thank God. For a while there I thought the PCM may of got fried in the fire, but it seems to working. In fact the Check engine light is on also.
Fix that later.

Now all this have taken place over a few weeks when I had time to work on it. Now that the truck is mobile, I have been driving the truck to the back of the shop to work on it and back to the back parking lot when I'm done. makes much easier instead of walking 300 ft one way to get a to tool or part.

One the times when I was moving it, I notice the right turn indicator turned on when I put the truck in reverse.
I may have a ground problem.

There is more but I getting hungry. I finish this when I'm done with breakfast.
 
Part II continue.

Okay, I took off the lower dash panel off to see what is back there. Nothing obvious. Crawl under the dash and happen to look at the brake light switch. The button is not touching the pedal, so the switch is on. That is why the third brake light is on. The back brake light wire must be open somehow.
Turns out the brake light switch has a quick adjust on its button. You pull the button all the way out and install it. (or push the brake pedal and pull the button out at the same time) as the pedal push against the button it bottoms out and adjusts itself to the farthest the pedal goes back. As the pedal goes away from the button, the button act like a regular switch. I must have pushed the button in too far when I changed the hydro-boost.

Next is turn signals. With the lower dash panel out of the way, I could check on the back side the fuse panel. Checked the wire coming off the flasher, 12.8 volts. That is about what my battery has been reading. It has not been getting a full charge. Okay the next connection is the "Multifunction switch" (turn, hazards, high beams, wipers). To get to it, I have to get the column covering off. Not really hard if you have a 20# torx bit that could go into 1/4" counter bore. I had only had at the shop torx bits that fit on 1/4" ratchet. The shank is to big it fit into 1/4" hole. I have 20# torx driver at home across town. That's it for one day.
I bring my whole torx driver set the next day and got one screw out okay, but the other hole had a wasp made mud nest. The truck sat around for a few months after the fire with the windows down. That must of been when the nest was made. It took ten minutes knocking the mud and wax out to get a good enough grip on the screw. I get the coverings off and can't get the connector off the switch. Try to to take off the switch so could get a good look at the connector, the switch is held on by a 20# tamper resistance torx. I have one at work and it is Saturday. I have something to do Sunday anyway. Monday, I bring the #20 tamper resistance torx bit from work and get the switch off the column. Turns out the connector is held on by a screw. Get the connector off and test the wire that is coming from the flasher. I have voltage. I test the wire from the brake light switch (with the brake pedal depressed), and I have voltage.

I decided to send voltage down the wire for the left rear turn signal wire to see if that circuit is working. The tail lights turned on. WTF.
I do the same for right side and the same thing happened.
I have ground problem.
So for recap. That one time I thought may of had a time delay lights, was the few times the rear brakes light circuit was working due to the always on brake light switch, but due to bad grounds, it was back feeding into the tail light circuit.
 
Finding that bad ground turned out to be an adventure. First, I take off the tail lamp thinking it be like a square body Chevy where the ground is under the tail lamp. There is no ground there. Next I look underneath. Don't see anything but the harness goes on between the frame and the spare tire. I look around the truck for the handle for the spare tire. I don't find it. Changing the spare is going to be fun in the future. I buy one those long 1/2" nuts (I think, it could have been 7/16"). The hex fits into the where the handle suppose to go, and I put a socket on the nut. I lower the spare tire and there is no ground.

Okay, I get out the book and read it a bit. As far I could tell, the ground goes all the way to the front of the truck into the harness under the hood.:screwy: The harness I had installed.

I don't know if I read the book right but is said the ground location is suppose to be by the horns where the battery to chassis ground goes. There is no ground there coming out of the harness. Whoever wrote the book screwed up. Okay, the ground wire in the chassis harness is a 12 gauge black wire with a blue tracer. There are two wires of that size between the fuse box and firewall. I pull the screws and clean the metal and re install the screws. I striped one of the sheet metal screws. Damn. I get out the drill, drilled it out, and install a rivet nut. With that taken care of. I went to pull apart one of the "under-hood" to "chassis" harness connectors apart and it came apart too easy.:eek1: It wasn't fully connected. So that was my problem. I checked to see if the blk/b wire has continuity to ground. It does. I spray contact cleaner on the connector and put back together making sure it was connected. I check my lights and tail, turn, and stop lights work.:woot:

I was fine with getting that fix and could get the rest fixed after the DOT inspection, but there where a couple of quick checks for I could do before I dig too deep.

In my research into HVAC, I learned there is relay in the system, and that relay is by the brake switch. It is easy to get to. I pull the relay connector off and I have voltage on the 30 and 86 sockets with the key on. 85 had continuity to ground. The same with 87 which should goes to the blower. Hmm, everything on the connector is good. What about the relay? It does not want come off the bracket easy, but to check to see if everything else works, a new relay should work and I have one. I plug the relay into the connector, turn the key, and the fan on. It works. I tied to run the AC but only the defrost works then I remembered I have non of the vacuum lines hooked up. Now I have to hook up the vacuum lines and get a relay that attach to the bracket.

Now one last fuse to check is the IOD (Ignition off Draw, I had to look it up.) fuse. I never was able to fully check this fuse before because it is little different. First, the fuse block had special plastic guard which makes removing the fuse difficult. Second, it has round edges doesn't have the "contacts" to check the fuse with a probe. Well, the reason it is different is because it is one those LED fuse my uncle had installed. Wrong amperage too. He had installed a higher fuse. In my earlier checks, I've noticed this fuse would have the LED glowing meaning it was blown. I just had too many other problems to concentrate on to justify spending 10 minutes trying to figure out how to get this fuse out of its guard. Well, it is now the last problem to solve. I finally figure out the trick on getting the fuse out of the guard and put in a regular, correct amp fuse in. As I pushed the fuse in, the rest of the buzzers started to work. I checked the radio and the incorrect time is showing. I turn it on and turned up the volume. It works. The dome works also.
I have have solved most of the problems with out tearing out the dash. Too bad I'm going have to do it anyway just to replace one turn indicator bulb. :doah:
So, to recap, I have replaced
3 fuses,
1 relay,
2 light bulbs, One of the third brake lights bulbs is burned out.
1 Multi-functional switch. I inadvertently replaced it before I fully got the rear lights to work. I thought it was bad because I could not get any of the flashers to work. This was the most expensive item.
 
Last edited:

Latest Posts

Top Bottom