Electrical

[mrmoose000]

My battery blew yesterday and I suspected it was the voltage regulator because the power was surging. I replaced both the battery and the voltage regulator on my 94 ford explorer limited. Now the car still surges past 18V(the red line) and I have no idea why?

Would replacing the brushes on the voltage regulator change the voltage output? It makes me uncomfortable to drive because I know I will eventually blow this new battery.

Any ideas???

PS: I did use the more expensive 130 amp regulator that limited requires

 

[jimbo74]

i would assume it might be the alternator then......

 

[mrmoose000]

wouldn't a faulty alternator produce NOT ENOUGH volts?

i am producing too many...

am i crazy?

 

[Opera House]

The alternator uses the 15A fused line to monitor voltage. Some have reported corrosion on the fuse terminals. If resistance in this line resulted in a 4V drop, the alternator would produce 18 on the battery. You are the first person I have ever heard of replacing just the regulator. I know there are just two screws that hold it on. I'd check the 15A alt fuse first. Then I would get a DVM to measure actual voltage at the battery, and regulator supply voltage at the alt plug Y/W.

 

[spindlecone]

Hope I am not stepping on this thread but was down at pepboys today, kid has an F 150 with the neg batt terminal, blown off the case, took out most of the top of the batt, the tech tells him it was caused because he started the truck with the AC in the on position, I do not see that as possible, But?

 

[jimbo74]

Hope I am not stepping on this thread but was down at pepboys today, kid has an F 150 with the neg batt terminal, blown off the case, took out most of the top of the batt, the tech tells him it was caused because he started the truck with the AC in the on position, I do not see that as possible, But?

it isnt... the people that work at pepboys, arent the brightest crayons in the box... hell i work at wheel works, which is in esscense the same thing, but i dont make crap up if i dont know what the problem actually is.... i do know that the ac being on will not blow up a battery... it might have been coincidental, but was not the cause

 

[spindlecone]

Jim
Thought naught also but never hurts to ask, BTW buddy of mine manages a wheelworks shop, they do darn good work and IMO opinion are very honest, My daughter picked up a nail on one of her brand new turanzas the other day, just before driving back to Santa barbara, 300 plus miles, takes it down to chevron, they plug the tire, comes back and I look at the plug, and also see SS wire where the plug is, Not driving on this tire I tell her, took it back to wheelworks, on sunday, we bought the tires there two days prior, am told they never plug tires as it is bad news to do so, he gave us anouther tire at no cost but said, pls do come back, good honest people

 

[mrmoose000]

The alternator uses the 15A fused line to monitor voltage. Some have reported corrosion on the fuse terminals. If resistance in this line resulted in a 4V drop, the alternator would produce 18 on the battery. You are the first person I have ever heard of replacing just the regulator. I know there are just two screws that hold it on. I'd check the 15A alt fuse first. Then I would get a DVM to measure actual voltage at the battery, and regulator supply voltage at the alt plug Y/W.

i'm not all that savy with my car...what else should I have replaced besides the voltage regulator? the 15A fuse? is that located in the fuse box? i'm assuming these are "duh" questions but i am not trained...if the 15A fuse doesn't fix the problem what else could it be?

 

[Opera House]

The alternator circuit is fairly simple. The only things that can cause the alternator to overvoltage are a bad regulator or low monitoring voltage. Resistance in fuse connections or alternator plug is one likely problem. There really isn't anything else except a bad regulator. So how much did the regulator cost?

 

[mrmoose000]

56 smackers at checker auto

rated for 95A or 130A alternator

how do i check for resistance at fuse and alternator plug??

which alternator plug? the 3 pronged one that connects to regulator...or that snap in one...or the screw on one?

 

[Opera House]

I'd check it visually first. Then I would look at the voltage on the Y/W wire of the engine wiring harness that plugs into the alternator. It should be the same as the battery.