View Full Version : Total electrical failure

06-11-2010, 01:00 PM
I don't have very much experience at all with working on 4X4s but I've gotten a lot of enjoyment out of fixing up my '76 FJ40. Unfortunately, A few days ago I went out take a drive and it wouldn't start. The starter wouldn't turn, the headlights, dome light, and hazard flashers failed to light, and even the instruments had failed. The ammeter sits right at the 0 line halfway between -30 and +30 and doesn't move for anything. I tried to jump it and when that didn't work I tested the battery with a multimeter which showed adequate charge. I've gone through and checked all the fuses, the fusible link, and terminal connections to no avail. Once, after leaving it alone in frustration for a few hours, I went and tried it. Everything came on, but when I tried to start it, the starter clicked once and everything went back to being dead.
I really appreciate any advice you guys have, and I apologize in advance for being such a newb. I really looked all over, but couldn't find anything.

06-11-2010, 01:11 PM
Check your ground connections on the battery. Make sure the battery has a good ground to the motor and frame.

Also, make sure the battery terminals are both clean and tight.

06-11-2010, 01:28 PM
Marco's advice is very good.

The cable from the negative post of the battery should be connected to the frame. Over time the moisture, dust and grime can work its way between the cable and frame and the current does not flow as smoothly as when the connection is clean. Scuff the mating surfaces (cable and frame) to remove the grime and then connect them back up. There is also a ground strap that connects to the lower bolt of the starter and runs to the frame - clean that up as well.

I've also experienced the grime on my fuse panel. Same cleaning principles apply, get rid of the grime and the current flows. When working with the fuse panel, disconnect the battery cable first thing and hook it back up after you finish cleaning.

06-11-2010, 04:12 PM
Yup sounds like a bad ground or loose/dirty terminal clamp. Check that and report back:)

06-11-2010, 05:57 PM
I played around with all those leads, but when I get home on Monday I'll pull 'em all off and really scrub them and the contact surface. I let you all know how it goes.

06-11-2010, 10:24 PM
Battery could also be dead, due to bad ground. But reading your first post. The first thing That popped into my head was ignition switch.

06-12-2010, 12:47 AM
I have personally experienced a bad battery cable itself. This was a non-OEM with the molded insulation going right up into the lead terminal. Inside, the strands of copper had become disconnected from the terminal. The tell-tale sign of the root cause was that if you turned the headlights on, then wiggled the cable there, the lights would intermittently blink on and off.

To rule this out, when the power is experiencing it's unwanted outage, bypass the battery cables completely with jumper cables and see what happens. Or just replace them with new out of spite.

As was written above, make darn sure your battery has a good ground to the frame. Unfortunately, 40s are cursed with a battery frame ground point just inside the passenger side fender well, where it can be exposed to everything from mag chloride to mud and all kinds of stuff. In my experience, once a good ground is established there they are usually good for a decade or two, but if that connection has been disturbed and not reconnected with proper metal surface prep it may only last a few years.

06-12-2010, 10:23 AM
1. One who is in a perpetual state of intoxication, living their life in a zombie-like state. (usual alcohol or weed induced, sometimes opiates as ...

06-15-2010, 03:55 PM
Running again! Thanks for the advice guys. I soaked all the leads in a baking soda/water mixture and then scrubbed the terminals, leads and ground point with a wire brush.
@ Rzeppa: My ground isn't in the fender well, it's in the engine; right next to the last spark plug. Is that not normal?
@ FJBRADY: Or someone who had a flash of inspiration while listening to Lil Jon and watching Van Helsing at the same time back in 2004 when that was cool....

06-15-2010, 04:46 PM
@ Rzeppa: My ground isn't in the fender well, it's in the engine; right next to the last spark plug. Is that not normal?

I'm pretty sure they didn't come from the factory that way, mine was the same when I got the truck - I didn't know it should have been connected to the frame. The first time I adjusted my valves I went over to Rzeppa's so he could show me how. One of the first things he noticed when we lifted the hood was the ground connected to the engine block, me promptly had me move it to the frame.

06-15-2010, 05:14 PM
On a stock 40 series (at least all three of mine) the factory put 2 big-a$$ grounds. The biggest one is from the battery negative terminal to the inside of the frame inboard of the right wheel near the shock tower. The second slightly smaller one goes from one of the 2 starter mounting bolts to the frame at that location. Factory wiring will be black with (faded and dirty) white stripe.