Wiring help

When I started working on my jeep (70 Commando, V6, auto) the lights didn't work. at all. I was able to get the headlights and front parking lights working, but rear lights and turn signals and hazards dont work. wiring diagram is useless as the wiring has been messed with a long time ago. What I need help figuring out is what wire in the steering column does what. the wires there are stock. colors are faded but I can still kinda make it out. any thoughts? I was able to get everything else wired working, the only things left are the fuel gauge and temp gauge, I can work on those after I get it "Street Legal."

 

The problem with the old wiring diagrams is they were printed in the color of the wire, so the wires are not labeled. I do know this much from off the top of my head (and from re-wiring a few Commandos)....

Dark green = tail lights L and R.
Tan = R turn / brake.
Yellow = L turn / brake.
Light blue = reverse lights.

Hope that helps you out.

 

Sometimes I found easier to replace the wiring and the contact system on the dash by in independant wiring. So I am sure that is the good one!

It is not 100% original look, but it really works well.

To check the connexion, I have a wire with a lamp and a small battery, so when the contact is good, it lights in front of my eyes.
It is not very clever, but it works.

 

When you say "messed with" do you mean that the original wiring has been hacked or that someone installed an aftermarket hot-rod harness?

If the wiring has been hacked, I suggest that you make a printed copy of the original wiring diagram and take it to your local library and blow it up in sections using a photocopy machine. Blow it uo really big, like 9 sheets, and tape them together. Buy a packet of 20 or so colored pencils, all colors. Then start tracing out the colors from the harness on the diagram. Even if the original haress was hacked up, it's very likely that most of the original wiring is still there.

Another thing - don't blame the hacked wiring for the lights not working too quickly. If the turn signal switch is messed up, or you have bad grounds, you will get strange behavior (maybe nothing) from the lights. If the Jeep has been sitting a long time, contact can be lost and the lights will stop working.

With electrical and wiring, you need to be systematic and focus on one circuit at a time. The turn signals and brake lights can be tricky, so I'd start with just tracing out the wires and see if everything is there.

The turn signal switch is likely an early GM style from before locking columns, same as the Wagoneer and J-truck from that era. Unfortunately I don't have any drawings or diagrams of that to help you with.

 

First thing I'd check is the plug that connects the rear wires, should be up around the left kick panel. Could be just dirty connections in there but most certainlt start at the column. Do your front turn signals light up at all or just the park lights?

 

definitely column related, check wires and turn/hazard switch

 

A few years back I bought my '69 Commando. The POs had unplugged about everything under the dash so I had a few days of trying to get things to work.
(A few other things like, you should actually tighten the fittings when you replace a brake line) but I digressed. The actual wires used are not too good. The insulation gets brittle and cracks allowing the copper wire inside to flex more and break. The bullet connectors used for the rear lights easily corrodes and the bit of rubber used to hold the pigtails to the base of the tail light bulbs sometimes fails. I did have to pull the steering wheel off and mess with some contacts in there so the turn signal lights would work.
Good luck. It's an ongoing struggle. lately, all of the lights work, the turn signals work but if the lights are on and I turn on the right turn signal, the RR running light goes out but the signal light still works? Everything worked well a year ago.

 

Just needs the ground cleaned on that side, that's all.

 

Um, done that. With the 3 studs, star washers and clean nuts, as said, the tail lights work and the turn signals work, just not at the same time. I'm sort of bumfuzzled about this. I don't think it is the steering column or ground. If I get a test light back there, everything seems to read correctly But it is usually the simple things.

 

I figured out what does what. took off the steering wheel and got my voltmeter out. I got the wires from the steering column, the switches in the column work, turn and hazard. so I'm just gonna take out all the "stock" wires and redo everything after the column. while I'm at it, I'm going to try to remove all the wires that don't go anywhere, then slowly work on replacing all the wires, or at least the brittle ones. Maybe make it like the stock wiring diagrams so it'll be almost accurate.

 

Glad to hear this. Was wondering if you had got it done since this thread had been hi-jacked and I didn't know if you would still be asking.

 

I'm sorry if you feel that I hi-jacked this thread. I just wanted to mention the wire and the connector issues of this era of Commando. The FSM worked for me.
Walt, if you will allow me. If you are going to rewire it, do a better job of protecting the wiring behind the rear wheels. One winter I had enough ice and snow built up that the weight unplugged the wiring to a tail light, probably not as much of an issue where you live. Also, make sure the wires going to the grille are secured. I had a problem one night when the wire loom flopped over on the exhaust manifold. Fun to fix in the dark.

 

ok, so I got my turn signals working, but now I can't get my parking lights to work. or the brake lights. which are wired all together "correctly." and my wiring diagram is pretty useless. Oh well. I'll wire it up seperately with something and move on to a different project.

 

Just got finished with adding a horn to Fussy, and just for snicks I checked the lights/signals and sure enough, the RF was off on both modes. Soon as I touched the connector under the hood, they flickered. So even though the connectors were cleaned last summer when I got Fussy road-worthy again, I had to clean the connection for the RF lamp once again.

Don't count out simple causes, traveling electrons are a unique lot! On any problem circuit you separate each connection in said circuit until you find where the continuity of the complete circuit fails.

Case in point, the trigger wire for the horn I just added. The 12 gauge wire tested good for B+ 12V with my test light. The trigger wire (black w/yellow tracer) would not ground when the horn button was depressed (test light clamp on the hot). I separated the 6 way connector under the dash for the column. I jumped the B+ to the trigger wire at where the horn should be. Using my test light checked the connector's terminal. It lit up. So now I verified the wire being OK from the 6 way connector through the firewall all the way back to the horn location. I pulled the cap off the steering wheel to access the horn trigger disc in the wheel. I reconnected the 6 way under the dash. Now I was back-feeding a hot through a wire that normally grounds, if it was shorted in the column, I would have seen sparks fly trying to connect the 6 way. That didn't happen. Then I took the test light to the wire that comes off the horn trigger at the uninsulated bullet connector. No light. Disconnected the other end of the wire at the base of the wheel (has a flat connector and a black insulating cover). No light! Then I disconnected the battery and pulled the steering wheel. Reconnected the battery and checked the brass stud that touches the steering wheel contact ring with the test light. Lit right up! So I check very carefully as I re-install the wheel and discover that the brass stud and wheel's brass contact ring have both worn enough to the point that no contact is made any more!

I disconnected my jumped wires and added a blob of solder to the end of the brass stud and cleaned off wheel's brass contact ring and carefully checked for contact re-installing the steering wheel. Looked good, so back to the trigger wire at the horn location with the test light, clamp back on the B+, light probe on the trigger wire. Pushed the horn button and ta-da, a bright light!

So there you go, what I did to get the problem circuit to now test good for normal function. I wired in a relay for snicks and I have a brand-used Ah-ooh-gaa horn on Fussy now. Things are looking up!:driving:

 

Yep, as said on an earlier post, wireing on a Commando can be fun. It can work one day and not the next. I fought for a fair amount of time with a contact in the turn signal switch in the column. Still working on how I can have lights and turn signals on the RR work but not at the same time. Yes, it has a good ground. It used to work. At least my horn works.

 

Yep, same reason Fussy has an old school bus lamp as a high mount brake light. Fussy runs me all about town and State this time of year and State Law requires "a brake lamp which illuminates whenever brakes are applied". I do not wish to be bothered by certain persons who attempt to dictate authority by claiming "You have a brake lamp out". If certain persons who attempt to dictate authority don't see that big 7" red lamp and know how to read what S-T-O-P spells out, maybe these same certain persons who attempt to dictate authority are the ones who should not drive.



All the rear running lights work, including the plate lamp. Both signals work running lights on or off, but I have no input for stop at the LR, so if I have my right signal on, there is no L brake light. Same situation happens with the signal arm in "neutral". Hence the easier fix was to add the 3rd lamp and switch it directly off the pressure switch so it always works whenever brakes are applied regardless of what position the signal arm is in. So far, so good and I've had a few certain persons who attempt to dictate authority pull up behind me at a traffic light.:driving:

 

I was thinking of installing a second set of amber lights as the parking lights. both front and rear. I found several that would work, and I can get them round and they almost match the style of the current lights. and easier to install. I also want to (one day) upgrade the headlights to something better, so that'll match too. Then I have to figure out the fuel guage and temp guage. and brake lights still.

 

So I got new lights, front and rear. The front ones are LED and have a separate circuit for running lights and turn signals. They work, but when I turn on the turn signal they don't flash, just stay on. Would using a new flasher bus fix the problem? Right now, when the turn signals worked, they were really slow to flash, and were on more than they were off. I'm thinking a bus that is on/off an equal amount of time would fix it. Thoughts?

 

LED lights do not load the flasher unit enough to allow the flashing to occur. They sell flashers just for the LED's.

 

Good to know, thanks!!