Intermittent alternator issue

[outkastnk]

Hey guys need a little help here!!!

I have a 96' Ford Explorer 6-cyl OHV (Not sure if thats XL or XLT, its got power seats?) that I've had for about 3 months. I'll get right to the issue.

When I bought the car the guy told me the alternator was new and sure enough when I looked at it, it looked new, no dirt, clean coils, so i took his word. I noticed a problem when I had left my lights on one day last week, had to get jumped, and noticed my car was not staying on. The next day I had my battery charged at an autozone, replaced my terminals on my battery because they were AWFUL, and put a new ground cable. While stripping the wires I noticed the positive cable looked good, no corrosion, fresh. Still noticed my battery light was on in my dash, and volt guage was low. **According to the alt/battery diagnostic test ran at autzone, before I changed the terminals, the alternator read "open diode" and the battery needed a charge. After, i changed the terminals, the alternator tested no good and the battery had less CCA then it was supposed to. The guy told me I could get by with the battery though. The next day though, it was all good!!! The volt guage was more neutral, and moving when I accelerated, and no battery light on. Yesterday I noticed when I fired it up the volt guage on the dash fluctuated from low to normal a few times, with the battery light coming on when it dipped low, then it seemed to work normal! It seemed as if the alternator briefly was turning on and off as the battery guage dipped back and forth. Then it stopped. As i accelerated the needle moved graciously up which means its charging the battery as it should right? As of today, the battery guage reads neutral when driving, and no battery light on. I do notice when I come to a stop though it gets a little low, but no battery light. Could this be because of the battery? Should the needle be moving at all when driving? Should it be completely neutral when stopped? Any ideas of what could be going on? I'm not real good with electicity...

I did some research on the forums and found some threads about a couple fuses that could be the issue. I checked the fuse in the PDB and in the dash for the alternator. Both looked fine, intact. Thanks for your help guys!!

 

[OneLever]

While stripping the wires I noticed the positive cable looked good, no corrosion, fresh.

Visual inspection of the wires is not very reliable. Measuring the voltage drop across them while current is running through them is a better way. The higher the current the greater a chance for you to detect a voltage drop from resistance in the wire. Here's a decent link on that: Link

According to...autzone...the alternator read "open diode"... After..the alternator tested no good. The guy told me I could get by with the battery though.

You can get by with a battery and no alternator for about a day. After which the battery drains and the car dies again. The autozone guy should not have said that.

the battery guage reads neutral when driving, and no battery light on. I do notice when I come to a stop though it gets a little low, but no battery light. Could this be because of the battery? Should the needle be moving at all when driving?

Two main things are happening here: You are altering the RPMs and jostling the wires around.

1. If you rev the engine in park does the battery voltage to move around?

2. If you coast and then hit the brakes pretty hard can you cause the voltage to move around?

3. Was the Autozone alternator test performed in vehicle or as a bench test?

 

[outkastnk]

You can get by with a battery and no alternator for about a day. After which the battery drains and the car dies again. The autozone guy should not have said that.

What I ment when I said getting by with the battery was the battery's condition. I didn't mean get by with the battery and no alternator lol.

Two main things are happening here: You are altering the RPMs and jostling the wires around.

1. If you rev the engine in park does the battery voltage to move around?

2. If you coast and then hit the brakes pretty hard can you cause the voltage to move around?

3. Was the Autozone alternator test performed in vehicle or as a bench test?

1. If i rev the engine in park yes, the volt guage does move.

2. I haven't noticed when I'm braking that the volt guage moves.

3. The alternator was tested in the vehicle, but I plan to do a bench test this weekend.

Since posting I haven't noticed the battery light on or a dramatic low in the volt guage. I do notice though at night, with my lights on, while parked, the guage reads a little low and my headlights do dim. What can this be attributed to?

 

[Turdle]

Bad battery connections
Weak Alternator



Stereo??????

 

[1AJeremyD]

Sound like you should replace the alternator. The diodes are probably getting tiered and the windings are shot too. I know on my truck the windings are all done (original alternator with 230K) so Im just going to replace the alternator with a 130amp one instead of the 95 amp. You can check them out here:

http://www.1aauto.com/1A/alternator/Ford/Explorer/-/-/1996

 

[OneLever]

I would recommend having the alternator bench tested. If it truly is new and in good condition, but tests bad while in the vehicle, then you are looking at wiring problems.

 

[outkastnk]

Thanks for the help guys. Yeah it sounds like a bench test is the way to go for now. I'll report back once I get that done. You guys rock!!

 

[outkastnk]

Overnight battery dead!

Well guys!

I woke up this morning to a dead battery! No lights on, nothing. I was super swamped this weekend with moving errands that I did not get a chance to pull the alternator.

I noticed Saturday when I drove the car (about 15~ min), the battery light was on and the volt guage was stuck at low. Alternator was not working i presume. It started "working" again right before I got home. I gave it a few rev's before i turned it off. Woke up today, dead battery.

Some searching on the forums I found that a bad alt can drain the battery. And a bad voltage regulator (which I read is inside the alt right?) can cause the issue. I also could have a bad battery, as like I stated before, the battery should be putting out 875 CCA and only tested at 700. Bad cell? I've read both issues can cause an overnight battery drain. Thoughts guys?

 

[outkastnk]

Upon further investigation I found out my stereo deck lights were on... while the car was off. Most likely drained my battery all day and night sunday, since I didn't use my car at all sunday. Me and a buddy pulled the fuse in the dash and it was still lit. We had to pull the center console out and pull the wiring harness out of it to turn it off. Plugged it back in and now my stereo doesn't work. Related issue? Total coincidence? F%#k me.

 

[OneLever]

What number fuse did you pull from the interior fuse panel?

You need to check for a parasitic drain on the battery. Here is a helpful link: Click

 

[outkastnk]

Got an update guys.

Pulled the alternator out, got it bench tested at the auto parts store... was only putting out 10.5 volts!! LOL. Needless to say I got a new alternator in and everything is working fine. My volt guage does not move and stays at a steady 13v~. Just to make sure I went ahead and bought a new battery too. Everything seems to be working great! I can't believe how easy it was to install the new alternator! 1st time explorer owner noob here.

I have no idea what happened with my stereo deck but I did notice my ignition column is getting a little loose. If you move it the right way, It will get the right amount of contact and start powering accessory. I can tell because if i fiddle with it with the door open I can hear the door ringer start to sound. Or I may be wrong.. Not sure how this would have shot my stereo deck but like I said its not working. Its like it has no power. I checked both fuses in the dash for "audio system" and the "radio/acc/other stuff" and they both looked good. No fuse on my deck either. Any ideas?

 

[OneLever]

Glad to see you got the main issue fixed!

I have no idea what happened with my stereo deck but I did notice my ignition column is getting a little loose. If you move it the right way... Any ideas?

The wiring bundle which runs up the steering column is commonly a source of short circuits and odd problems. When you move the steering wheel up and down it bends the wires back and forth. Over time this can lead to the insulation around them wearing away and shorting out through the column. Might be worth just taking the top column covers off and looking around.

 

[1AJeremyD]

I'm happy to hear you got your problem resolved .

I stinks having to bit the bullet and just buy a new alternator but those are extremely easy to install as you saw.