always something...failing alternator?

[outlander]

There are a few grounds under the dash--instrument panel, others.

You should use your ohm meter to measure the resistance on all of the sensors to see if the resistance is too high, indicating poor connection.

What is the procedure for this?do all the sensors share grounds?

 

[joe_peters]

Charging can range from 13.0 to 15.3 volts depending on the ambient temperature.

 

[outlander]

Thanks for all of your input joe.

 

[outlander]

Started it up the other day and lights started diming,voltmeter dipped down as low as 9volts then back up to 14 all the way to the parts store.Got there and it was acting fine so it passed their test....
Kinda seems like the alternator acts up when its cold and then acts fine when up to operating temp.
If it was a bade connection you would think it would do it all the time....
Checked battery cables at the battery and they are clean and tight...went as far as removing them and cleaning/oxguard.
Anyone else have a alternator do what mine is doing?

 

[lawsoncl]

Start with the basics. Is the belt properly tensioned?

 

[outlander]

yes.

 

[BrokenSockets]

If it is dropping as low as 9, it could be bad brushes in the alt. When mine went bad it would start low, pop up to normal after a minute. It started to take longer to pop up to full voltage, then started dipping randomly, then hovering between low and normal, then needed a wack with a small hammer to start working, then needed a wack with a BIG hammer to start working, then crapped out.

 

[Matthew Currie]

In the early stages of brush failure, that hammer whack is a good way to confirm the problem. If the voltage pops back up when you hit it, it's pretty likely to be the brushes.

 

[87manche]

In the early stages of brush failure, that hammer whack is a good way to confirm the problem. If the voltage pops back up when you hit it, it's pretty likely to be the brushes.

this.

re: the blower motor ground, it doesn't, which is why turning it on makes the volt gauge drop substantially because the gauge is measuring the potential, and you added a crap ton of extra current to it's ground. Add one by getting a ring terminal, cleaning the blower motor housing to bare metal under one of the mount bolts and sandwiching the ring terminal under there. Ground it somewhere handy with something like a 10Ga wire and your blower motor will work a million times better and not drop the dash voltage/dim the instrument lights. and make sure you check that HVAC connector I mentioned earlier. Mine was a freakin fire hazard. I replaced with individual spade connectors. It's PITA, but good luck finding the proper connector.

 

[outlander]

If it is dropping as low as 9, it could be bad brushes in the alt. When mine went bad it would start low, pop up to normal after a minute. It started to take longer to pop up to full voltage, then started dipping randomly, then hovering between low and normal, then needed a wack with a small hammer to start working, then needed a wack with a BIG hammer to start working, then crapped out.

Thanks!!
That was the info I was looking for.This alt is fairly new,good thing it has a lifetime warranty.I wish I could get it to fail altogether so it will test bad and they will give me a new one...sick of messing with it.

Guess those brushes start working normal once they get heated up???

 

[outlander]

this.

re: the blower motor ground, it doesn't, which is why turning it on makes the volt gauge drop substantially because the gauge is measuring the potential, and you added a crap ton of extra current to it's ground. Add one by getting a ring terminal, cleaning the blower motor housing to bare metal under one of the mount bolts and sandwiching the ring terminal under there. Ground it somewhere handy with something like a 10Ga wire and your blower motor will work a million times better and not drop the dash voltage/dim the instrument lights. and make sure you check that HVAC connector I mentioned earlier. Mine was a freakin fire hazard. I replaced with individual spade connectors. It's PITA, but good luck finding the proper connector.

I put a new blower motor and resistor in last week and all is fine now....volts barely drop at all even on high.Was a total:flame: hazard with the old blower though!!!

 

[outlander]

Update:
While doing some troubleshooting yesterday i noticed a symptom that I somehow missed.At idle and up to approximately 2000rpm everything is fine.
As soon as the rpms go above 2000 the voltage goes all over the place and the lights dim.

I took it back yesterday and had them hook up their portable tester and made sure I reved it to 2000rpm while they had it hooked up and even had the guy look at my voltgauge while it was dipped down in the red......result???
It passed!!!!

The guy said that their portable tester wont detect a bad diode...wtf???Thats retarded.He said that it takes an average of output,not a low or high.

So I took the thing off and am getting ready to take it back to put on the bench tester(that will detect a bad diode)

I'll be back shortly with the verdict.Im so friggin done messing with it Im tempted to open the case and snip wires so it will test bad so they will give me a good one under warranty

 

[joe_peters]

Here is some reading for you on Delco Remy alternators: http://www.tpub.com/content/constructionloader/TM-5-3805-258-24-2/css/TM-5-3805-258-24-2_32.htm

 

[lawsoncl]

I took it back yesterday and had them hook up their portable tester and made sure I reved it to 2000rpm while they had it hooked up and even had the guy look at my voltgauge while it was dipped down in the red......result???
It passed!!!!

Let me guess - Autozone? Where lifetime warranty usually means you'll be replacing it frequently. That really sounds like a bad alternator to me. Their bench test isn't much better than their portable testor (ie, voltmeter).

 

[outlander]

Mission accomplished!!!
As soon as they spun it up on the bench it was a fail.I got a new one and all is well....
Thanks to all that helped out on this one...

I can only pitty all the people that take their vehicles in assuming a bad alternator only to have their little portable tester tell them all is well.Imagine those who have less mechanical knowledge running around in circles because they believe that their problem is else where!!!!