Confirm my suspicions - alternator / regulator (1 Viewer)

[Alibaster]

Came out to the battery dead in the cruiser one day. Weird but okay. I jumped it and ran it and thought it was okay. Dead again two days later. Weird. The battery is pretty old so I got a diehard platinum. Dead the next day. Out comes the multimeter and I’m pulling 3amps. I jump it and check across the terminals and I’m at 18v. I notice all of my turn signals are burned out, which were my last non LED bulbs. I did notice my positive terminal was cracked so I replaced that, same issue. Radio no longer turns on when truck is on and the ABS light comes on intermittently. Inside reads at 18v when running.



Based on zero knowledge and skill, I am lead to believe the regulator in the alternator is defective. I have no idea if this is the original or not, I would assume so. Plan is to buy a reman denso and hope for the best. Is there anything else I am missing before I do? I used multiple multimeters and same results. I have the battery disconnected now so I can move it if needed.

 

[ramangain]

This is a MUD technical forum, so I'll just come out and say it ....

You should throw (away?) endless money and rebaseline all fluids, filters, plugs, TB/WP, all bushings, hubs, flanges, axles, etc. Then tackle your actual issue.

 

[Alibaster]

Agreed. I’m going to buy 15 alternators and go quad quad quad quad quad battery.

 

[MongooseGA]

Sounds like a voltage regulator to me.

Don't forget to grease your drive shafts and U-joints while you're in there.

 

[Alibaster]

Sounds like a voltage regulator to me.

Don't forget to grease your drive shafts and U-joints while you're in there.

I had already planned to pop it off from the frame real quick and por15.

 

[Mike NXP]

I would think you are on the right track as long as all of your connections and grounds seem to be in decent shape.
>> Don't forget to replace heater t's while your in there...jk

 

[Alibaster]

Well I put in a reman Denso alternator and now it’s charging at 12v across the terminals. So that’s great.

 

[KillerBox]

Hopefully the new alternator fixed your problem but, if it happens again try this.

1.) Turn engine off
2.) Go remove the Alt-S fuse by the battery
3.) Make sure the fuse isn’t blown
4.) Reinstall the same fuse
5.) Start the engine & see if your voltage readings are right.

If so you have electrical corrosion that you can’t see on that fuse holder that needs to be cleaned or it will continue to happen.

 

[Alibaster]

Yeah I am going to check all the fuses tonight and see whats what. I'm hoping I don't have to pull the alternator again and reseat the plug, but I will if I have to. If that fails, I'm pulling the bumpers and sliders and burning it in place.

 

[KillerBox]

Yeah I am going to check all the fuses tonight and see whats what. I'm hoping I don't have to pull the alternator again and reseat the plug, but I will if I have to. If that fails, I'm pulling the bumpers and sliders and burning it in place.

My little fuse check can be done in about 1 minute so It is a super easy to check.

 

[Alibaster]

Yeah. My only concern is that it was clearly "charging" before I put the new alternator in. So I'm hoping I didn't jack up the wiring harness when I was twisting the old one around in there. I also think the plug only goes in one way, but I don't know for sure.

I drove it around the block and used all my accessories just fine. I left it hooked up over night, so I will see if the parasitic draw is truly gone when I get home today.

I'll have to do some reading on ways to determine if the alternator is charging without pulling it as well.

 

[abuck99]

Parasitic draw is unavoidable- how much is controllable to a point. Less than <50mA is your target. Over that then start identifying the circuit drawing amps when keyed off. You can first check the fuses in the engine room junction box by quickly testing between the two small exposed terminals on top of each fuse to see if there is current/amps running through that circuit (no need to remove fuses).

 

[KillerBox]

I think the most common parasitic draw problem is with the CD or DVD player trying to eject the disks even if there are no disks even in them.

 

[Alibaster]

Well my alternator was overcharging at over 18v and burned up all my turn signals and the radio fuse. I also had a 3amp parasitic draw. Replaced alternator and the draw is gone, but so is the charging it seems. So back to it.

Its just highly annoying because prior to this I have had zero issues. Everything works, no leaks. Perfect condition.

 

[Alibaster]

I'm updating this for search purposes for people in the future if they have the same problems. I took the alternator off again today to investigate the wiring harness. The 3 wire connector seemed a little ****ed up and the retaining clip portion of it broke off. It slid easily in and out of the alternator. It looked like it should still be making contact but clearly something is wrong because its not charging at all at the battery. So I ordered a new connector to see if that fixes it. The fuses looked good to me. I have a feeling its the cabling somewhere.

 

[Alibaster]

Success. Replaced mangled connector and new alternator shines bright.
And I’m a pro at taking off the alternator now