Charging/Battery Light - Please Help...

[Ludigdrums]

'81 Vette w/an electric choke and no computer.

I really need some help. I posted this thread http://www.corvetteactioncenter.com/forums/showthread.php?p=393969#post393969 with not much luck as far as replies.

Without re-explaining the whole story, which can be found i nthe above link, here's where I'm at right now:

The Charging Light stays on with the engine on, and as the RPM's increase, so does the brightness of the light. The voltage gauge reads around 14-15 and shows charging. The battery is fine, and I've been going through all of the connections and tracing wires. Checking the continuity of the Heater Choke Relay and cannot find anything wrong with it.

Everything was working fine, no problems except for the light being on and the buzzing of the choke relay. Well, now, unfortunately, I no longer have the relay buzzing, but the light is still on, and now my power windows, seats, and the blower all do not work. Checked all fuses.

This is driving me nutso!!! Please help. I don't know what else to really do.

Thank you!

- Jeremy

 

[bill81vette]

the only thing i can think of off the top of my head is to check your ground connections and make sure they are all tight. other than that i'm clueless sorry

 

[Ludigdrums]

Thanks for at least responding...I was beginning to think that my posts weren't being seen!

I just came back in after a full day of troubshooting and going through almost all of the wiring in the car. I'M STUMPED!!! Everything looks good...I've gone through every ground and cleaned with a wire brush as well as electrical contact cleaner. Totally refurbed the Starter harness and replaced fuseable links, removed each individual connector pin, and wire brushed those as well. The main fuse block by the drivers side firewall, I removed and cleaned all of those contacts as well.

I also had both dash consoles out and again, cleaned all contacts and such.

Through this process, now I have no power windows, seats, or blower motor. Everything else works fine.

Went through every fuse. Nothing was wrong.

My main problem seems to be somehow stemming from the #1 brown wire from the 2-wire alternator connector. According to the shop manual, when removed from the alt., that wire should have 2-4 volts. Mine has zero, and the manual says that indicates an open in that wire. Well, I've tested for continuity at both ends of that wire and it is fine. However, when the car is running, that wire is getting 20+ Volts. Which is also going into the choke/heater relay.

I even tried a different alternator. No go!

Come on all you electrical guru's....what am I missing?!?! It's gotta be something simple at this point!

Thanks for reading!

- Jeremy

 

[lone73]

The brown wire...

If I'm thinking right that brown wire is usually just a sense line to tell the alternator how much of the voltage it's putting out is making it to the remote wiring locations of the vehicle. The lower the voltage on that wire the more the alternator is supposed to put out. You say you got 20+ volts on it? Wow! I'd say that might be related to your problem or it might BE the problem. If your's is like my '73 (and I think the alt part is pretty close) that terminal *receives* input from the brown wire. Your alternator looks to be raising the voltage on it on it's own. There's no way you could be getting 14v out the alternator and sensing 20+ back on the sense line. You'd be making electrical energy.

If you start the car and measure the voltage at the brown wire terminal with the two wire plug unconnected what do yo get? What's the DC volt output at the back of the alt measured with your meter?

later
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[Ludigdrums]

With the car running and the 2 wire disconnected, the brown terminal reads 7.8. The funny thing is that when I plugged it back in, it was reading 1.5 until I increased the RPM's then it quickly jumped up to aboiut 17-18 at idle, and around 21 with faster RPM. Both the #2 red wire and the red bat wire read about the same, 14.5 at idle, to a max of 15 with increased RPMs.

I cannot figure this out. I've literally been through almost everything twice. I replace the window circuit breaker, thinking that might be it. Not. I found a blown fuse, but that was just for a solenoid on the hood that opens an air flap thing. It was plugged into an accessory outlet in the fuse panel. Replaced it hoping it would do something, but didn't.

I feel like it keeps getting worse and worse. No windows, seat, blower. Now the alarm started freaking out (not disengaging with the clicker).

This is driving me nutso, but I am determinded. It's gotta be something dumb.

Thanks for the help so far...please keep it coming!!!

- Jeremy

 

[Bob Chadwick]

I lost my windows and the gen light came on. I also lost a couple of the gauges. The 10amp gauge fuse had blown and these items were all connected somehow.

I had the electrical troubleshooting manual and by reviewing the items that weren't working I found out that the common itew was the instrument fuse.

 

[Ludigdrums]

Hmmm, I've read about this 10amp Guage fuse before...but cannot find it. Mine is a 20 AMP. And what's weird is in the text, the shop manual says 10A, but in the diagram is shows a 20A.

The weird thing here is that the problem all started with the generator light coming on, and the heater/choke relay buzzing. Everything else was working totally fine. It has progressed to no power windows/seats/blower motor, and most recently the alarm started acting crazy.

Speaking of crazy, I'm already past that stage. My mind is drawing a blank as I have gone through almost everything I can think of. Terribly disappointing!

Keep 'em coming please! Thanks again!

- Jeremy

 

[lone73]

What do the other ends of both the brown and the other wires on the 2 wire connector got to? I mean physically in your car what are they connected to? You say you ohmed out the brown wire and it was at zero, with the car running?

 

[Ludigdrums]

The brown wire goes to the generator light, and then to the choke/heater relay underneath the shifter. I check it with the car off, ignition off, from the starter 2 wire harness to the choke relay harness without the relay pluggin in. I've also done it with the relay out. It doesn't read 0, but close, like 0.2.

The red wire connects to 2 other red wires, one which goes back to the fuse block, and the other which goes to the underhood lamp harness.

By the way, the brown wire is on circuit #25.

 

[lone73]

Very difficult to do long distance diagnostics but I'll take a look at my schematic when I get home in a couple hours. Sounds like if you lost function of several things while messing around in there you might've yanked something loose. Maybe something loose inside the fue block. You got an aftermarket alarm in that thing?
lone73

 

[Ludigdrums]

Thanks man. Yes, I have an aftermarket alarm...Viper...I installed it, no problems, and that was almost a year ago. I've disconnected it for the time being. The previous owner must have bypassed the factory alarm, as well as computer. But, from all the wire patches, it looks like it was done correctly (ie: solder, elec tape, etc.).

I'm just in the process now of taking the fuse box out from the inside as well. Cleaned those contacts...everything on the inside looks good.

I'm going to test for power from the outside fuse box connector.

This is very weird, as it started out seemingly simple, and has compounded itself into way more. It feels very non focused because I already went through all the logical stuff.

I appreciate your responses. This will be something when/if we get this figured out!

Thanks again!

- Jeremy

 

[curtis]

I still think it is a ground wire hooked up with the battery wires on the starter. when I did this to my car , some things wouldn't work, others wouldn't shut off, the underhood light switch went up in smoke, everything was just screwy. That high voltage you get from the alt sounds like when you do a full field test on the alternator. If the internal regulator is bad you usually get too high voltage output. If that happened it is possible to burn out a fusible link. wish I could be ther to help you check it out. you got a real challenge here. good luck

 

[Ludigdrums]

Thanks Curtis...I have had the starter harness out yet again, and everything is perfect. EVen better than before. Wire cleaned everything...put new fuse link for good measure. Everything!

One of my many random thoughts, is it could somehow be the starter itself. The main screw that the + Bat cable goes to seemed a bit strange to me. When you take the bolt and wires off, it's got another bolt at the bottom, and when you turn this one, you can loosen the whole screw, but not take it fully off. You can also tighten it, and it tightens fine. But, I've kinda ruled this out as the starter is working fine.

A bit of recent history that might help is how this all started. One of the wires at the starter was giving me an intermitent problem where I would loose all power, except for the underhood light, and not be able to start it. It wouldn't even crank or anything. When I would touch the wires at the starter. Wala, it would be fine. So, that's what first prompted me to look at the starter harness, and repair those connections. I also noticed that the 2 wire alternator harness's brown wire was almost totally frayed, so I got a new connector and replaced the old one.

Everything was fine right off the bat! It wasn't until after I drove it for 10-20 miles that I noticed the Bat light come on. Then I noticed that buzzing sound which came from the relay.

That's how it all started, and now my vette's interior is all practically out to expose all of it's insides!

Boy I'm tired!

- Jeremy

 

[bill81vette]

jeremy...did the wire you replaced get frayed again?..you might want to take the starter and alt to like auto zone or whatever you have on LI and have them tested just to be sure they are ok
just a thought!

 

[curtis]

this sounds kind of like more than one problem.. sort of sounds like the regulator in you alternator may be bad or the alternator is shorted and you get voltage out just like doing a full-field test on the alt. loosing accesories sounds like link or fuse . I saw somewhere where you had tied some wires together at the starter. In the diagram I have it only shows 2 red wires and a PPL (purple?). the only black in the area is a ground. my diagrams are in a Haynes Manual. this has to be extremely frustrating. somebody has to have the answer for you. in the meantime, make sure your fire insurance is up to date.

 

[curtis]

the bolt (terminal) on the solenoid you talk about where the bat wires hook most likely has nothing to do with your problem. the end of the bolt on the inside of the solenoid is just a contact for the diskbehind the spring. loosening the nut only lets you remove the thing. It is a serviceable part on the solenoid.

 

[bill81vette]

this sounds kind of like more than one problem.. sort of sounds like the regulator in you alternator may be bad or the alternator is shorted and you get voltage out just like doing a full-field test on the alt. loosing accesories sounds like link or fuse . I saw somewhere where you had tied some wires together at the starter. QUOTE]

i kinda got that impression as well when i was reading his 'bit of history'i also think that one problem maybe compounding the other..IMO

 

[Robin7TFour]

jeremy, you have a blown diode pack in the alternator. that's why it was charging but still the light stayed on. if you're good with tools you can do it yourself,but there are a couple of tricks to do.if you decide to do it let me know and i'll walk you thru it


ahhh yoda,, disney has taught you well.

Robin

 

[lone73]

Maybe I'm lookin' at this schematic wrong but it appears to me the brn alt wire goes thru a connector and becomes tan and proceeds to what looks to be the blower resistor pack. You ohmed it and got near zero so I'm assuming I'm wrong. All I have is a Haynes book. What color is the wire at the opposite end from the Alt.

Robin, he said he tried a rebuilt alt and got the same results.

later
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[Ludigdrums]

Thanks for all the replies!

bill81vette - the wire isn't frayed...I actually replaced the connector with a new one, so the wires are perfect. I was thinking of doing the alt and starter, but I don't feel those are the problem as the starter is less than a year old, and I tried a different alt.

curtis - the shop manual shows that 2 of the red wires connect together and then connect to the starter with a fuseable link. Then there is another red wire. The Purple wire connects to the other post on the starter. So, along with the main + wire, there are 3 other wires that connect to that main post.

Robin7TFour & bill81vette - I think I've ruled this out because with the 2 wire connector disconnected from the start, I get readings from the brown wire that are not what they are supposed to be. So, I don't see how the alt can affect that. Plus, I tried a different alt already as lone73 said.

lone73 - the brown wire stays brown the whole way. From the alt, it goes to the fuse block. From there, it goes to the connector in the back of the center guages cluster for the gen. light. From there, it goes back down to the choke/heater relay. And that's it. The diagram actually shows an A and B for circuit # 25 which is what this circuit is. The wire from the fuse block and from the relay both meet at the center guage connector.

I really really appreciate all the help so far. Please let me know if you think I'm wrong with anything. We'll get to the bottom of this!

- Jeremy