N/A Automobile Electrical Help

t0r0nad0

t0r0nad0

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PJ Gustafson
I have a 2002 XE 4 Cyl 5-Speed that has recently developed an interesting and annoying "personality quirk", if you will. One night when I was driving home, my A/C Blower suddenly slowed down and my lights dimmed. At the same time, my Battery and Brake lights on the dash flickered. It's been doing this since then, and has gotten worse. A couple of days ago, I was driving through a dark area with my high-beams on - it did its little trick, but this time the lights were flickering so fast, it's almost as if they were a solid on. Then, my airbag and ABS lights started flickering intermittently, but independently of each other and the battery and brake lights, the latter two always flicker together. The strange thing is, this rarely happens when it's just sitting at idle - it mainly happens when I'm accelerating or at cruise. Any ideas out there?
 
Loose wire(s) or connectors in the wiring harness, or bad voltage regulator, which is inside the alternator.

I say that almost totally unencumbered by the thought process, ..well with little experience anyway.
 
First things I'd check would be the ground wire between the engine and body, and the positive cable from th battery to whatever distribution point it goes to first. Sounds like you are getting very large variations / pulses, and that they affect beyond any one circuit.

Also, long shot, but you could have a damaged battery- check to make sure both posts are securely attached (the actual lead post / electrode that goes in to the battery). I had the darndest time with this problem on a Toyoto in Peru once. It was a beee-otch to troubleshoot, especially about 200 miles from the nearest shop.
 
lemme express my ignorance ... what make is an XE?

My wife's Chrysler 300 is experiencing the somewhat infamous (at least among 300M owners) "Chrysler light show" where the dash lights flash between dim and bright. The published fix is, after tearing most of the dash apart to reach the offending wire bundle connector, reseat the connector 3 times (yep, 3 ... not 2, not 4, but 3 ...) then unplug, reapply dielectric grease and seat the connector one more time. Reassembly is the reverse of the above.
 
Sorry, it is a Nissan XTerra XE model... I cross-posted from an XTerra owner's forum where the make and model were a given, I just needed to specify body style. Sorry for the confusion.

Good ideas guys, I'll check the battery posts, wires, and grounding tonight. If it's a bad voltage regulator, do I need to get a whole new alternator for that?
 
I would post the results of the google search, but it's a circular queue ... first hit is yours on nissanhelp.com ... that won't help you much, I'm afraid! :)
 
t0r0nad0 said:
Sorry, it is a Nissan XTerra XE model... I cross-posted from an XTerra owner's forum where the make and model were a given, I just needed to specify body style. Sorry for the confusion.

Good ideas guys, I'll check the battery posts, wires, and grounding tonight. If it's a bad voltage regulator, do I need to get a whole new alternator for that?
Click to expand...

You would, unless the alternator has a replaceable module. I would look for bad connections first. You should get a light if the voltage regulator goes nuts.

BTW, do you have a voltage gauge? You could get one for $10 that plugs into the lighter socket. When you get the dimming you could see if shows dropped voltage or an intermittent.

I recently was lent a former-police FBO crew car where the alternator light was on. They told me it would be fine. Luckily it did have a voltmeter. When I saw the voltage drop steadily with the lights on at night I pulled over before the engine quit.
 
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I don't have a voltage gauge, but I'll look into stopping and picking up one like you described. My assumption is that while the lights are doing their thing I'm getting a discharge, but when I sit at idle, everything is working fine and I'm probably getting a charge. The voltmeter would be good to verify.

I don't have any problems starting the thing, nor does the engine seem to be affected by these electrical antics in any way.
 
PJ sounds to me like you have a Alternator going bad, at Idle the brushes make good contact, At speed they are jumping off the comutator. My suggestion is take it to a shop where they can test it at Idle and have them test it at say 2000 to 3000 RPM.
Dave G.
 
Shipoke said:
PJ sounds to me like you have a Alternator going bad, at Idle the brushes make good contact, At speed they are jumping off the comutator. My suggestion is take it to a shop where they can test it at Idle and have them test it at say 2000 to 3000 RPM.
Dave G.
Click to expand...

:target: My thought exactly Dave.
 
Shipoke said:
PJ sounds to me like you have a Alternator going bad, at Idle the brushes make good contact, At speed they are jumping off the comutator. My suggestion is take it to a shop where they can test it at Idle and have them test it at say 2000 to 3000 RPM.
Dave G.
Click to expand...

Dave, alternators do not have commutators, they have slip rings which are much less likely to fail. Still possible, though....

-Skip
 
Also - if you do not want to spend money on the check, Autozone or Checker will test it for free. Just walk in and tell them what's up.
 
When you are checking the wires and battery, also check the belt for tightness and glazing. A bad belt could cause slippage. If that occurred you might have enough belt traction to provide a small alternator output current.... sufficient to charge the battery at low loads but discharging the battery at high loads. When your battery voltage is very low, you can see the gremlins that you report. How does it crank? Enthusiastically or like it is dog tired?

-Skip
 
I had a 96 Grand Cherokee that I thought was electrically possessed.

First, the door locks would lock or unlock on their own. Then, the A/C compressor would turn on at will, or not turn off. Then, the power windows started going up and down by themselves.

I took it in, expecting large expen$ive problems, but they put it on a battery tester first, and yup, the battery was going bad. The car still started fine, though.

The service mgr said the car uses various computers, and everything is connected on a buss. As the battery starts to die, weird voltage spikes cause the devices on the buss to think they've been activated.

I doubted this, but after the new battery, all was normal again.
 
I've got a Pathfinder.

The symptoms (other than "not at idle") describe precisely what happens when the voltage gets too low - in my case, when the alternator cr^??ed out. THe voltage gets low, the computer acts up, and various lights dim and flash. At some point, the fuel pump and injectors (EFI) stop working. And then it dies where it is. Hopefully you get off the highway.

Nissans use an integrated alternator/voltage regulator. You replace the whole unit for something on the order of $150 parts plus labor (I swapped it myself, pretty easy on the Pathfinder).

You MAY have a bad ground off the unit, possibly a bad positive lead off the alternator, or something may be sucking a lot more juice when at highway speed.

But I'd bet on an alternator issue.

Easy way to test: get a cheap voltmeter, put it across the battery terminals, start the car and read the voltage as you rev the engine. If it's less than 12.5-13 with the lights, AC and defroster on, then you can pretty well bet on the alternator.
 
Some of the things you describe are on a car's version of an "essential DC Bus", such as air bags. These things, like most shouldn't be impacted by anything except the battery and its connections to the car. Check the positive connection (by wiggling) at the battery and starter and wherever else it goes, and of course the negative conection where it binds to the chasis. Just grab a handful and see if it's loose.
 
wsuffa said:
Easy way to test: get a cheap voltmeter, put it across the battery terminals, start the car and read the voltage as you rev the engine. If it's less than 12.5-13 with the lights, AC and defroster on, then you can pretty well bet on the alternator.
Click to expand...

Or the easy and old fashion way...see if a screwdriver or wrench will stick to the back side of the alternator.
I don't recommend this method.
 
Well, I took it to the Zone - Auto Zone, and had them hook up their machine. They saw that when at idle, there was barely a charge going to the battery. When I turned on everythign electrical, output went down a whole volt. When I hit the gas, it went down a whole other volt. The verdict? Bad voltage regulator in the alternator, resulting in the need to change the alternator. Car is presently in the shop having this done, to the tune of $386.00 installed :'( . But, it's a brand-new alternator with a lifetime warrantee, which is good since I plan on having the car for a long time.
 
kevin47881 said:
Or the easy and old fashion way...see if a screwdriver or wrench will stick to the back side of the alternator.
I don't recommend this method.
Click to expand...

I like this method- it can, if used properly, allow you to actually weld a screwdriver or wrench to the alternator, thus ensuring that such tools are readily available!
 
t0r0nad0 said:
Well, I took it to the Zone - Auto Zone, and had them hook up their machine. They saw that when at idle, there was barely a charge going to the battery. When I turned on everythign electrical, output went down a whole volt. When I hit the gas, it went down a whole other volt. The verdict? Bad voltage regulator in the alternator, resulting in the need to change the alternator. Car is presently in the shop having this done, to the tune of $386.00 installed :'( . But, it's a brand-new alternator with a lifetime warrantee, which is good since I plan on having the car for a long time.
Click to expand...

Man, I can't believe how much it costs to have an alternator installed. That's what, a $49 alternator, and $330+ for labor? Yikes.

Holy cow, nevermind, that's an expensive alternator. $191.49 from the zone. Yikes!!!
 
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t0r0nad0 said:
Well, I took it to the Zone - Auto Zone, and had them hook up their machine. They saw that when at idle, there was barely a charge going to the battery. When I turned on everythign electrical, output went down a whole volt. When I hit the gas, it went down a whole other volt. The verdict? Bad voltage regulator in the alternator, resulting in the need to change the alternator. Car is presently in the shop having this done, to the tune of $386.00 installed :'( . But, it's a brand-new alternator with a lifetime warrantee, which is good since I plan on having the car for a long time.
Click to expand...

:D

Not bad for "completely unencumbered."
 
SkyHog said:
Man, I can't believe how much it costs to have an alternator installed. That's what, a $49 alternator, and $330+ for labor? Yikes.

Holy cow, nevermind, that's an expensive alternator.$191.49 from the zone. Yikes!!!
Click to expand...

Yeah, I was a bit surprised too. I shopped for alternators online yesterday and found some cheaper, and had asked the garage to shop around too. He said that he did find some that were cheaper, but since I planned on keeping the car for a while, he recommended I get the one with the lifetime warrantee. If I was planning on getting a new car in about 6 months or so, then he'd say the cheaper one was fine.

I probably could have done the install myself, except for a couple of things:

1) It's near the bottom of the engine, so I would need to either have ramps or a lift.

2) I just don't have time to do it and I needed it done today - especially since it got so low this morning that my engine started to quit, until I pulled into a parking lot, shut off all the electrical equipment, and let it idle for a while. I didn't want to risk it quitting on the freeway on the way home.
 
I spoke too soon...

The garage just called me. They said that with the old alternator, it was reading "Low Voltage". They put a new one on. The reading actually got worse! So, they're going to try another alternator, just in the off chance that the new one they put on there happened to be bad. If they get the same result with another alternator, then they need to dig up some schematics and try to trace the problem down. Unfortunately, they won't be able to get another alternator in there and on the car tonight, but the good news is that they're open tomorrow. So, I'm without a car tonight and I live 25 miles away. Good thing the gf is driving into town tonight so that we can go to a friend's party.

The really bad thing is that I now have no idea how much this is going to cost, so there goes my flying budget for the month. Maybe I'll get lucky and they can just put the original alternator back on there and I'll just get charged for the labor.
 
Ni$$an$ use expen$ive alternator$. Ask me how I know. :(
 
SkyHog said:
Man, I can't believe how much it costs to have an alternator installed. That's what, a $49 alternator, and $330+ for labor? Yikes.

Holy cow, nevermind, that's an expensive alternator. $191.49 from the zone. Yikes!!!
Click to expand...
Ever look at aircraft alternators? Huge cost for the same $49 alternator that you put in the car.
 
Well, they put a second alternator on there with the same result. They then traced the wiring back into the dash and quickly found a loose connection, which they then plugged in. They bench-tested the old alternator and found that it did indeed give a bad charge, so they left one of the new ones on the vehicle. The end result is that for 0.428 AMU's, my car is running just fine again.
 
As I mentioned, last Monday the Sable wouldn't crank. Plenty of juice, just nothin' from the starter. I dropped nearly $500 for the towing and install of a new starter.

Let's put this way. The $500 and a full tank of gas doubled the book value of the car.

I mentioned to a guy this weekend and he said on Fords you just have to give the starter a whack to free up the solenoid. That makes sense to me. Of course, I can't imagine that my mechanic would happily sell me a new starter after he gave the old one a whack to start the car. :dunno:

Oh. I have another $350 worth of transmission hoses on order.

I have to decide to set a tipping point against my "If it lasts another year or two" plan less than the dead engine or tranny I had mind.
 
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