Uh oh..dash warning lights!

[Megell]

Hi Everyone,

I hope you can help me with a problem. Recently while driving my ABS, BRAKE, STOP LAMP and BATT dash warning light would come on and I could feel a slight difference in performance. My question (s) are does anyone know what would cause those four lights to come on and off intermitanly (sp?)?. It's happening now several times a day while driving.

I carry a voltmeter thinking I can take an alt. output reading while the dash lights are on but they go out and the alt reads like 14.1 ISH . Of course I get back in and drive off and they come back on again.

Would the alt. regulator cause those particular 4 dash lights to come on instead of just the batt. dash light.

Sorry for long post but I kinda need to fix this myself as this is one of those lean times.

Thanks for any help everyone.

Mike

[valvestem]

Hi Everyone,

I hope you can help me with a problem. Recently while driving my ABS, BRAKE, STOP LAMP and BATT dash warning light would come on and I could feel a slight difference in performance. My question (s) are does anyone know what would cause those four lights to come on and off intermitanly (sp?)?. It's happening now several times a day while driving.

I carry a voltmeter thinking I can take an alt. output reading while the dash lights are on but they go out and the alt reads like 14.1 ISH . Of course I get back in and drive off and they come back on again.

Would the alt. regulator cause those particular 4 dash lights to come on instead of just the batt. dash light.

Sorry for long post but I kinda need to fix this myself as this is one of those lean times.

Thanks for any help everyone.

Mike

 

I may be wrong but, the ABS system pulls quite a few amps when functoning. So based on that knowledge, plus the batt light to me equals the battery is failing. The 14.1 volt reading at the alt means it is working OK, the batt is prolly not accepting a charge anymore. The reason the lights go out on stopping is I THINK the ABS is not pulling amps while in "Park". Maybe a "load test" on the batt would be best, and go from there. Most auto parts stores will do it for you FYI.

[johnceggleston]

Hi Everyone,

I hope you can help me with a problem. Recently while driving my ABS, BRAKE, STOP LAMP and BATT dash warning light would come on and I could feel a slight difference in performance. My question (s) are does anyone know what would cause those four lights to come on and off intermitanly (sp?)?. It's happening now several times a day while driving.

I carry a voltmeter thinking I can take an alt. output reading while the dash lights are on but they go out and the alt reads like 14.1 ISH . Of course I get back in and drive off and they come back on again.

Would the alt. regulator cause those particular 4 dash lights to come on instead of just the batt. dash light.

Sorry for long post but I kinda need to fix this myself as this is one of those lean times.

Thanks for any help everyone.

Mike

 

year make model and miles would help, but yes, a bad alt will light up the dash.

[Megell]

I may be wrong but, the ABS system pulls quite a few amps when functoning. So based on that knowledge, plus the batt light to me equals the battery is failing. The 14.1 volt reading at the alt means it is working OK, the batt is prolly not accepting a charge anymore. The reason the lights go out on stopping is I THINK the ABS is not pulling amps while in "Park". Maybe a "load test" on the batt would be best, and go from there. Most auto parts stores will do it for you FYI.

 

 

 

I just now started the car and the 4 lights were on and stayed on. I popped the hood and hooked a voltmeter from the output post on alt. and grounded the black lead on the alt housing and the reading was 12.1 v. I revved the engine and the voltage did not increase.

The battery is new last June as well as the alt. Cables are clean and tight.

The battery reads 12.46 volts at this time.

Thanks for your input.

Mike

Edited January 7, 2010 by Megell

[Megell]

year make model and miles would help, but yes, a bad alt will light up the dash.

 

 

Thanks John, 91 Legacy SS, 5spd. 195K, well maintained. Recent new batt. and alt.,

Mike

[Suzam]

When you say the alternator is "new" was it a rebuilt unit? If so it could be bad and needs to be replaced.

 

Also check the belt tension.

[Sonicfrog]

I second the alt. All dash warning lights on seems to be an accepted standard, though I have no idea who it was that decided to make it a standard. I've dealt with both bad batteries and alts in the various cars I've owned over the years and that sequence of conditions has always been the result of a failing alt.

 

And yes, I'll freely admit I've owned a few non-sub's over the years. Don't hate me.

[Megell]

When you say the alternator is "new" was it a rebuilt unit? If so it could be bad and needs to be replaced.

 

Also check the belt tension.

 

Alt. was a rebuild by a Alt/starter rebuild company here in Tucson. It came with a readout sheet showing output details etc; and a 1 year warranty.

I called the company and they said it sounded like the internal Reg. was Spiking and to bring it in.

Mike

[Megell]

I second the alt. All dash warning lights on seems to be an accepted standard, though I have no idea who it was that decided to make it a standard. I've dealt with both bad batteries and alts in the various cars I've owned over the years and that sequence of conditions has always been the result of a failing alt.

 

And yes, I'll freely admit I've owned a few non-sub's over the years. Don't hate me.

 

 

It's interesting to note that the original alt. failed and never did give me ANY kind of light or indication until the car started running crappy and died in the middle of one of the busiest intersections in Tucson. Cost me an additional 300 + because of the red light that appeared and photo radared me. I coasted to a stop just past the intersection and nothing. Where were those lights when I needed them?

And now the lights are telling me the alt. is bad....hmmmm!

I wonder how hard it would be to hook up a real amp gauge instead of the batt. light?

BTW, what's up with turbo car without full gauges, no boost gauge either. Oh well.

Mike

Edited January 8, 2010 by Megell

[Megell]

I removed the alt. last nite and returned it to the supplier for testing. Since the problem has been intermittent, I was afraid that the problem might not show up when they tested it. 15 minutes of testing and a hardcopy readout sheet of it performance were all within specs.

OK, I put it back on, making sure everything in clean and tight and start the car and everything is normal, until less than an hour of driving, the lights came back on.....and off..etc;

That's the way I'm driving it right now with the lights coming on and then off. The battery, so far, seems ok at upper 12 volts. I'll keep an eye on it to see if it starts discharging.

The supplier also said that my 91 legacy's alternator does NOT have a built in regulator. Is that true? Is there a voltage regulator that's not part of the alt. that I'm not aware of.

Mike

[Cougar]

The regulator is built into the alternator. I don't know why their information is stating that is isn't built in.

 

The warning lights are part of the exciter circuit of the alternator so they can be tested when the key is turned to ON. Even though the test stated the alternator is ok it has an intermittent problem and it needs to be replaced. The brushes may be going out on it.

[nipper]

Bench testing is such BS. Have them test it on the car, thats really the only way to test it. They need to use an analog (looks like a big metal cheese greter with jumper cables) tester.

 

You have a bad Alt and may have to buy another one that is built from a reputable shop. I dont know what the online suppliers get for a reubuild for your year (www.1stsubaru.com) etc.

 

If you are not getting full output above 1800 rpm (14 voltish) and everything on, the alt is fried.

 

nipper

[Megell]

The regulator is built into the alternator. I don't know why their information is stating that is isn't built in.

 

The warning lights are part of the exciter circuit of the alternator so they can be tested when the key is turned to ON. Even though the test stated the alternator is ok it has an intermittent problem and it needs to be replaced. The brushes may be going out on it.

 

I was surprised that he said external reg. He also asked this other guy Chris (that sold me the one I've been using for six months) and he also said that my alt. that he sold me did not have internal reg. and of course that it checked out ok. I believe them about the alt. readings but except for the fact that it can take up to an hour of driving and then the 4 dash lights appear and then go out There seems to be no real set pattern to when they come on.

Tucson Alt. Exchange seems reputable and they were helpful when I returned it for a test. ... OH man, As I type this I remembered that I called TAE beforehand and told them over the phone the symptons and..this same guy Chris said..to me over the phone that it was probably the internal regulator spiking.

I will give him a call Monday to see if Subaru reg. is in or out.

Meanwhile I keep driving armed with my trusty voltmeter.

Mike

[Megell]

Bench testing is such BS. Have them test it on the car, thats really the only way to test it. They need to use an analog (looks like a big metal cheese greter with jumper cables) tester.

 

You have a bad Alt and may have to buy another one that is built from a reputable shop. I dont know what the online suppliers get for a reubuild for your year (www.1stsubaru.com) etc.

 

If you are not getting full output above 1800 rpm (14 voltish) and everything on, the alt is fried.

 

nipper

 

 

Hi Nipper, when I called them about the alt. I asked if I could just drive it down and have them check it on the car ..(hopefully while the warning light are on and not off, because the voltage changes as well as the rpm of the engine when they go on and off) thinking I could just install new one in parking lot if needed. They said they do not have a mechanic to perform such a task. I thought, well, I got a voltmeter and I can show you that the alternator drops down at least to 12.1 v. and as high as 17 and 19v.

Nipper, maybe I not testing right. I am connecting the + lead to the large wire on the alt. and grounding the black leak on the alt. housing or nearby engine parts. Am I doing something wrong?

Mike

[Megell]

Bench testing is such BS. Have them test it on the car, thats really the only way to test it. They need to use an analog (looks like a big metal cheese greter with jumper cables) tester.

 

You have a bad Alt and may have to buy another one that is built from a reputable shop. I dont know what the online suppliers get for a reubuild for your year (www.1stsubaru.com) etc.

 

If you are not getting full output above 1800 rpm (14 voltish) and everything on, the alt is fried.

 

nipper

 

 

Hi Nipper, when I called them about the alt. I asked if I could just drive it down and have them check it on the car ..(hopefully while the warning light are on and not off, because the voltage changes as well as the rpm of the engine when they go on and off) thinking I could just install new one in parking lot if needed. They said they do not have a mechanic to perform such a task. I thought, well, I got a voltmeter and I can show you that the alternator drops down at least to 12.1 v. and as high as 17 and 19v.

Nipper, maybe I not testing right. I am connecting the + lead (of the voltmeter set to 20v DC) to the large wire on the alt. and grounding the black lead on the alt. housing or nearby engine parts. Am I doing something wrong?

Mike

[nipper]

I would test it at the battery, but your way isnt horrible, your voltage regulator is out of wack. Them not having a mechanic nor having the tester (which is a basic tool for an alt shop as it only takes 1 minute to run a test) is inexcusable.

 

At that high a voltage you are damaging the battery.

 

I dont like this shop.

 

 

nipper

[Log1call]

The shop sounds like it's bluffing really. I'd say it's your alternator that's the problem. It could well be that heat under the bonnet is a factor and why it tested ok on the bench.

 

Your readings of nineteen volts... are you sure your gauge is accurate? Nineteen volts is mighty near enough to blow bulbs. Nineteen volts will definitly wreck your battery too.

 

I think your alt is crook but I suspect your gauge as well to tell the truth. Perhaps it's time to try another shop.

[Megell]

I would test it at the battery, but your way isnt horrible, your voltage regulator is out of wack. Them not having a mechanic nor having the tester (which is a basic tool for an alt shop as it only takes 1 minute to run a test) is inexcusable.

 

At that high a voltage you are damaging the battery.

 

I dont like this shop.

 

 

nipper

 

Thanks Nipper, I have tested the voltage at the alt. and at the batt. terminals as well as the batt. cable ends all seperatly while engine running and all working normally read in the middle 14's, which, seems to me like it should work all goe's south when the dash lights come on. So far, the batt. is still maintaining high 12 volts so I'm still driving with this on and off situation.

Has anyone installed an aftermarket amp gauge on a Subaru's that dont have full gauges? It sure would make it easier to diagnose this problem.

Mike

[hankosolder2]

I once had a similar problem with a Honda. Alt would charge fine for the first 1/2 hour of driving and then poop out. Dude at the parts store SWORE UP AND DOWN that alternators are never intermittent. I finally got ticked off, pulled the alternator, attached the alternator to a 120V wall cord and plugged it into the wall, brought it back to the store and told them "I think it finally quit will test bad now." The replacement alternator fixed the problem, so my diagnosis was definitely proven correct!

 

Nathan

 

PS: I would not advise doing something simialr unless you are familiar with electrical safety procedures.

[Megell]

I once had a similar problem with a Honda. Alt would charge fine for the first 1/2 hour of driving and then poop out. Dude at the parts store SWORE UP AND DOWN that alternators are never intermittent. I finally got ticked off, pulled the alternator, attached the alternator to a 120V wall cord and plugged it into the wall, brought it back to the store and told them "I think it finally quit will test bad now." The replacement alternator fixed the problem, so my diagnosis was definitely proven correct!

 

Nathan

 

PS: I would not advise doing something simialr unless you are familiar with electrical safety procedures.

 

 

 

It took me awhile to quit giggling and reminds me of previous similar experiences when one has to revert to plan B. I once had toaster that seemed to only work when it was near a sink, so I put it in my bath water. It quit working completely and after I got out of the hospital, I returned it with no problem.

[nipper]

I once had a similar problem with a Honda. Alt would charge fine for the first 1/2 hour of driving and then poop out. Dude at the parts store SWORE UP AND DOWN that alternators are never intermittent. I finally got ticked off, pulled the alternator, attached the alternator to a 120V wall cord and plugged it into the wall, brought it back to the store and told them "I think it finally quit will test bad now." The replacement alternator fixed the problem, so my diagnosis was definitely proven correct!

 

Nathan

 

PS: I would not advise doing something simialr unless you are familiar with electrical safety procedures.

 

Got to love a man with style

 

:lol:

[hankosolder2]

Thanks!

[uniberp]

Also, check your battery ground strap. The end on the block for sure. This sounds like it could be a simple aging issue.

 

Bench testing is such BS. Have them test it on the car, thats really the only way to test it. They need to use an analog (looks like a big metal cheese greter with jumper cables) tester.

 

You have a bad Alt and may have to buy another one that is built from a reputable shop. I dont know what the online suppliers get for a reubuild for your year (www.1stsubaru.com) etc.

 

If you are not getting full output above 1800 rpm (14 voltish) and everything on, the alt is fried.

 

nipper

[Megell]

Also, check your battery ground strap. The end on the block for sure. This sounds like it could be a simple aging issue.

 

 

UPDATE: Problem solved, I got tired of my engine performance going away when I most needed it traffic because of the Alt lights coming on and off bench tested it with a bit more determination. A quick trip to part store confirmed no more intermittent reliability problems. Supplier also confirmed and gave me a new one with another year warr.

Thanks for everyone's help.

Mike