Amp light on without key on or even in

[TroyaCantrell]

Say, just put in the new alternator in my '66 CJ6 this weekend and the amp light in the gauge cluster came on and stayed on even without the key in.

It got late so not much trouble shooting but does anyone have any ideas?

Also only getting 12.58 vdc from the alternator. It has the external voltage regulator.

 

[jswatson0917]

When my parking brake is set mine will come on.

but, since yours is on with out the key being on someting may be wired up incorrectly. What kind of condition is the wiring behind the dash is it nice and neat or is it one huge giant rats nest? Was the light on before the alternator swap?

 

[TroyaCantrell]

It is kind of a mess under there. I have a complete new harness but was hoping to get the rig drivable for the summer.

The lamp was not on before the swap but the old unit was burnt in places and had no amperage.

 

[jswatson0917]

I would try to find a wiring diagram for your Jeep. Sounds like you have a hot wire running to that light.

 

[JR74CJ5]

I would try to find a wiring diagram for your Jeep. Sounds like you have a hot wire running to that light.

That light is hooked in to the charging system. It's the exciter wire indicator.

I had to put a resister in to stop back flow of current through the wire when i replaced my alternator.

It would stay running while the key was off and out.

Not exactly the same problem, but semi related.

It took a case of beer (well between the two of us) and a multi-meter and the whole day for me to track down my other issues (burned out wire)

 

[TroyaCantrell]

Thanks all, I dug up the wiring diagram and it is wired wrong. So of the three wires coming from the voltage regulator one goes to the field, this has a connector, of the other two one goes to the ground post and one goes to the aux post and then to the gauge. It was previously wired with both leeds going to the two ground posts on the alternator.

According to the diagram the RED wire goes to the aux post on the alternator. Problem is I don't have a red wire. I have black with white stripe and a greenish brown one. The third is for the field and again has the connector so that one is right. Just not sure which wire is + and which is - .

 

[JR74CJ5]

If you have a multi meter, do a continuity test on the negative correct?

I have had the problem with different color wired voltage regulators too...


~ JR

 

[TroyaCantrell]

If you have a multi meter, do a continuity test on the negative correct?

I have had the problem with different color wired voltage regulators too...


~ JR

JR, continunity from where to where?

 

[JR74CJ5]

JR, continunity from where to where?

Hmmm... good point... I was thinking of finding which wire is ground, but that will not work as you are supplying ground to it...

Look up the wiring diagram for the regulator you got. Should have a manufacturer's name on it or the box (assuming you just bought a new one? but now that I read your post again, maybe not...)

I'll bet we didn't take a picture before removing the old one (alternator) right? (I always do that now after a couple of "these" so you can tell what color wire went where later...)

So your regulator only has 3 wires? mine has 4... They were different colors only between 1 wire so wasn't hard to figure out...

I'm at a loss bud...

I could make a guess, and say anything with black on vehicles should be ground related, but... that's an expensive guess for me to make for you...

If you do hook it up backwards, there's a chance it may blow I am not sure...

If it were me I'd try the black with white stripe as ground, but I have a lot of new parts on my jeep for a reason

Snap a pic and post it of what you have going on...

 

[TroyaCantrell]

Thanks, same thoughts I was having about the ground. I also ordered a new regulator and am hoping the pigtail has a red and black wire on it so I can tell which is which.

I labeled and numbered all the wires as they came off the old alternator so I know I have them the same way, they were just wrong before, which is probably why the alternator was fried. For a few bucks I just figured I would replace the regulator too and now that I know it is wired wrong it is almost surly cooked as well.

Appreciate the help.

 

[TroyaCantrell]

Thanks again for the help. As I hoped the new regulator had the proper color coded wires allowing me to track it down. The black/white wire was the ground wire. It is now installed and seems to be working...

I am getting 13.89 vdc from the alternator at idol. it should be at about 2000 RPM to test full output and my battery was down to about 12.4vdc and it should be fully charged for testing as well.

 

[JR74CJ5]

Nice!

Glad it's working out for ya!

Now I have to try to figure out mine...


~ JR

 

[TroyaCantrell]

Yeah saw that. Can you get it up higher with a new mount?

 

[JR74CJ5]

Thinking so... Looks like this would be pretty sweet... Bulltear Bracket

Now the question is, do I want to buy it done already and nice? Or...



~ JR

 

[TroyaCantrell]

For $70. I would buy it, but then I don't have gear or knowledge to weld it. Haven't welded since shop class in high school and that was a long time ago.

 

[JR74CJ5]

yes the pricing is not too bad!