Dash lights on - charge, oil, A/T temp, etc - a definitive fix?

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IdahoDoug

IdahoDoug

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I'm doing maintenance on my bro in law's 93 w/ 335,000 miles on it and put a new PS pump on. Started it up and all the idiot lights are on. Read the threads and some crazy solutions like spray out the alternator seem to work but I'm the cautious type and don't want to trash his alternator. Otherwise, there were no "aha" moments like this ground or that wire that people found, so kinda vague fixes. Also, people put starter kits on which also seemed unrelated.

I put it on the charger overnight so it will be full charged so I can see if it's a low voltage issue but others found this not to be their problem.....

Anybody find a specific problem and fix it to see this go away??

DougM
 
Could you have bumped one of the connections on the alternator while replacing the PS pump? They are pretty close together, it wouldn't have been hard to knock something with a ratchet handle.
 
Yeah, I should have elaborated. There are a few connections in the area and I disconnected the little ground wire that goes on the intake manifold, and the coil high tension wire because they were in the way of getting the PS pump in and out. When the lights all came on on startup, I rechecked these, then pulled them apart and cleaned them and also pulled the alternator's connector out and cleaned it. Then I studied all the connections in the area to ensure they weren't disturbed. So I kinda feel like I did my homework before posting in terms of my having knocked something loose.

So we're back to the truck simply having an issue that others have faced and they've had a variety of fixes. I'm loathe to rinse out the alternator but while waiting for any input here I'll be doing a coolant flush outside and if no advice surfaces I'll end up doing that. Eeek...

DougM
 
In my case, it was the starter contacts. I had that happened twice last year. Decided to try the new starter contacts first (because they are cheap). It seems to fix the problem with a new starter plunger and contacts.
 
like said above, check for loose connections.

Do you have a scangauge? If so, use it to see what the alternator is putting out. When my dash lite up, i hooked up JFZ80's scangauge and found my alternator was not charging. Replaced it and went ahead and upgraded with photoman's bracket. That fixed mine.
 
It's not charging and battery's fine. So I'll be doing a dreaded hosing of the alternator. I may also have some spare used alternator brushes. Bummer - it would be an unusual 90 degree day today to hang over a hot engine....

DougM
 
Kev - which wire is that? One of the wires in the alt's square plug? Or is there another white wire. All his are wrapped, so not immediately clear which wire you're referencing. Thanks!

DougM
 
IdahoDoug said:
Kev - which wire is that? One of the wires in the alt's square plug? Or is there another white wire. All his are wrapped, so not immediately clear which wire you're referencing. Thanks!

DougM
Click to expand...

The big charge wire that goes on with the nut, it goes to one of the fusible links at the battery.
 
OK - status so far:

Charged the truck all night and in the morning no change so battery seemed ruled out.

Later in the day, I brought it to an auto parts store where they offer bat/alt checks and the bat checked out fine, but the alternator was not charging (he got a little over 11 volts on his tester).

Got home from that and did the dreaded hosedown of the alternator. Soaked it with a spray bottle of detergent first, then hosed it off/out liberally from the front and rear. No change.

Checked Kevin's wire and it's got over 12 volts from the battery so that seems OK.

Removed the back of the alternator and the brush set looked worn but nothing wacked out. I did not remove them, used a dental mirror. Minor metal dust in the brush holder so I sprayed it out with brake cleaner. Put it back together and started the truck - no change. So that seems to rule out the brushes in the alternator, because the brake cleaner would have cleaned out any grime to get good brush connections. And the guys who've had success turning off the warning lights with washing the alternator were most likely cleaning out the brush contacts, right? This is a key point to me, so looking for input.

So, that's where I'm at. I'm not an electrician so this is not a good troubleshooting opportunity for me. If anyone here has auto electric experience and would like to do the 80 community a favor it would be great if you could get a diagram and suggest a few things. More and more people are getting this issue and the 'fixes' are all over the map which makes me think the fixes are covering up some issue (a bad common ground that all 80s suffer from, etc). This fix would definitely end up in the FAQ section.

No other symptoms. No stumble, stutter, etc. Starts and runs excellently. Interestingly, the ammeter gauge flicks slightly when the blinkers are used but other accessories like the high beams, brake lights, full heater don't move it as much. Some other guys with this "all lights on dash" issue reported the same. Even using the 4 way emergency flashers doesn't move the needle, which is interesting considering it's essentially the same circuit as blinkers but twice the load??

Thanks in advance.

DougM
 
Sounds like you have pretty much confirmed that it's dead. If you have a starter/alt repair shop close they can test it out of the rig. But it's probably time for a replacement.
 
I guess I'd agree that I've confirmed the alt is not putting out but I'm thinking it's because of a connection rather than the unit itself. It worked fine when I drove it to my house. I replaced the PS pump. When I started it, the alt was not putting out. So it seems like something I did as opposed to the brushes going from working fine to 100% dead and not even responding to an overly aggressive cleaning.

Since others have experienced this exact phenomenon, I think something is going on besides the unit dying for no apparent sudden reason. Like I disturbed the wiring harness and something nearly shorted from age finally shorted.

What say ye?

DougM
 
Just an FYI, the solution of new starter contacts for the same symptoms, is because if the contacts stick closed and the engine starts, the starter remains engaged and makes the dash lights go wonky. It doesn't seem that this will be relevant to your particular situation.
 
IdahoDoug said:
I guess I'd agree that I've confirmed the alt is not putting out but I'm thinking it's because of a connection rather than the unit itself. It worked fine when I drove it to my house. I replaced the PS pump. When I started it, the alt was not putting out. So it seems like something I did as opposed to the brushes going from working fine to 100% dead and not even responding to an overly aggressive cleaning.

Since others have experienced this exact phenomenon, I think something is going on besides the unit dying for no apparent sudden reason. Like I disturbed the wiring harness and something nearly shorted from age finally shorted.

What say ye?

DougM
Click to expand...

Starter/alt repair shops and some parts stores have testers that can run/test the alternator alone, out of the rig. If you want to confirm it's death that would be my next step.
 
Just FYI and maybe to save you some busted knuckles and a few curse words.... i replaced the brushes on my alternator when i was having the same issue. Worked for about 4 days and i got the same issue again. That's when i stepped up and used the bracket i had sitting on the tool box from photoman, went to the local junk yard and got a nice sequoia alt. Buttoned it all up and i've been good so far! Been a year and counting.

Just saying, maybe go ahead and replace it instead of trying to rebuild it. With over 335,000 miles, i would say it has done it's service. Let it rest in peace.
 
Yeah, I know replacing it is a temptation, but honestly I am having trouble that I took the truck on Wednesday, replaced the PS pump on Thursday and starting it up the alternator chose that day that second to die.

Coulda happened - yeah. But I'm thinking there's something chafing or shorting from me sliding the PS pump up and out of the engine bay. There's that huge engine harness atop the left frame for instance. Just bugs me and I was hoping someone would say "check this" and solve it.

DougM
 
I'm with the rest of the bunch that say either brushes or replace alternator, Doug. It's really pretty simple - if the alternator isn't putting out the 14 volts needed to charge - there isn't too many options unless there's a short. Pretty slim chance of that unless you've got a buggered up or melted harness. Just chalk it up to coincidence. I'd try new brushes first. My .02 & tally up the posts.
 
IdahoDoug said:
No other symptoms. No stumble, stutter, etc. Starts and runs excellently. Interestingly, the ammeter gauge flicks slightly when the blinkers are used but other accessories like the high beams, brake lights, full heater don't move it as much. Some other guys with this "all lights on dash" issue reported the same. Even using the 4 way emergency flashers doesn't move the needle, which is interesting considering it's essentially the same circuit as blinkers but twice the load??
Click to expand...

It sounds like the alt to me, but interestingly enough I had almost the exact same symptoms. My battery crapped out on me (which I knew it was, because it wouldn't hold much of a charge, even leaving just the CD player going for 15 minutes would kill it enough so it wouldn't start).

Today I started my truck, just barely started. Should mention that we had our first 100+ day yesterday, and the truck was sitting in the sun all day long, probably finished it off. (I've been putting it off for months.)

While driving to the store, it seemed fine (other than just barely starting). Went in and got some stuff, came back out and it fired right up. As I was driving to my next stop--while idling at a light--the CD player cut out (powered off). It came back a moment later, then did it again. About that time the red idiot light started blinking and the ammeter gauge started bouncing up and down (above and below the min line). I killed everything (lights, AC/Fan, stereo, etc) and revved the engine a bit to bring it back up. Limped to Sears and picked up the PM-1 battery as a replacement.

Few things I've noticed since I replaced the battery. The ammeter gauge does not move like it used to (used to rise under heavy acceleration, drop when idling). It barely moves (almost too small to see) when blinkers are on. When operating multiple windows at a time it doesn't move as much from the power draw.

Most battery places will test it for free. Probably something worth checking out.

Again, like I said, sounds like an Alt. I never got all 3 lights on the dash like you did, but I never tried to start it when it was having issues. :meh:
 
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