Lights Out....

So I put a new fuel tank in, she (1974 cj5) is running good. The fuel gauge even works. So I'm driving on my way to work tonight and a guy pulls out in front of me.
I take evasive action and drive around him to prevent a collision, as I lay on the horn.
The entire jeep goes dark and I roll to the roadside.

I didn't have time to check under the hood, I'll look her over tomorrow. I had to drive my wife's car to work.

I did disconnect the negative terminal when I was doing the gas tank, and I just twisted it on finger tight. I'll check that first but don't know where to go from there.

 

Thanks, will check.

 

It's not the battery terminal.

 

Use your test light and make sure you have battery voltage on all three wires on the starter solenoid terminal that has the positive cable connected to it. If you do then check the 6 wire plug connector in the engine compartment. The C12 wire changes to A12 at this plug and the A12 wire goes to a splice terminal under the dash which feeds all the power to the ignition switch.

 

Almost sounds like a blown fuse... but normally the horn and lights are not fused.

 

'74 is the last year for inline fuses. The wiring diagram (and TSM) is online at www.oljeep.com Looking at the diagram, power for the lights comes from the starter solenoid (C12), through the firewall bulkhead connector (A12) and to a big splice under the dash where it branches out to the lights, horn, and ignition (A12B, A12A, and A45 resp). I don't see any indication of a fusible link, though there could be one in the harness bundle between the solenoid and the bulkhead.

Sorry I'm repeating some of what Walt wrote.

http://oljeep.com/gw/74_tsm/22-7-CJWiringDiagram.pdf

If you still have trouble, print out a copy of the diagram and start testing with your meter or test light. Be patient and systematic. Start at the battery and work you way toward the lights until you find the problem.

 

Neither the horn nor the lights work, I have a mechanic coming over tomorrow afternoon that used to own a 67 CJ5, to help me.

 

Thanks, will do.

 

Does the ignition switch need to be in the 'on'
Position?

 

I had problems with my fuel gauge (rear tank, 1971) and it makes always electric problems.
Maybe this is not related... but

 

Oh yes, it's very new. I checked it with my multi meter, 12 volts.

 

Have you checked the cables at both their ends - at the ground connection and starter relay, etc. ?

A bad gound would kill the entire system.

 

My Jeep mechanic found the issue, it was a loose corroded connection on the first prong behind the spedo to the Amp light.

Till next time, thanks guys.