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This is what I have . I have a 2 amp draw at the battery. I narrowed it down to a possible alternator, maybe? I have 1 large red lead connecting to the back of the alternator and a plug with a yellow and blue connector. If I disconnect the 2 pin connector at the alternator my 2 amp load at the battery goes away. I have power at the 2 pin CONNECTOR on the blue wire also if I disconnect it. All these wires run to what looks like a relay(4wires) that looks new.( NOTE>>all of these tests were with the car not running and the key out.) Should I have power at the 2 pins ON the alternator running or not? How can I troubleshoot this? Thanks
 

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The relay which you described is your voltage regulator. It sounds like it might have a short causing the draw. You should only have power at the red wire when the car is not running??? (I'm not sure if the blue wire is charged with the car not running). Is the alternator output 13 volts or better at the battery, when the car is running at idle? Try this....Swap out the Regulator with a different one and see if that stops the draw. If you get the same results.....the regulator is good.
 

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the red wire goes straight to the battery and has power all the time...

But the blue and white ones should not. Both pass thru the regulator, and I always forget which is which... but they are labelled on the back of the alternator. The one labelled "F" is the field winding, it turns the alternator on. The other goes to the gen light. Niether should have poiwer with the key off.

Could still be bad regulator, or something wrong in the run circuit of the ignition switch.
 

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As JimM suggested, the external regulator is bad. Voltage relay in the external regulator is struck closed causing current flow.

Also could be the adjustment internal of the external regulator is too tight.

If you find the external regulator is bad, visit your local parts store and get a Wells P/N VR715 regulator. Its the electronic version of this mechanical regulator. Keep the filter from the OE one, the little can on the side, and change the top from the OE and your replacement will look OE.
 

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Discussion Starter #5
Everett#2390 said:
As JimM suggested, the external regulator is bad. Voltage relay in the external regulator is struck closed causing current flow.

Also could be the adjustment internal of the external regulator is too tight.

If you find the external regulator is bad, visit your local parts store and get a Wells P/N VR715 regulator. Its the electronic version of this mechanical regulator. Keep the filter from the OE one, the little can on the side, and change the top from the OE and your replacement will look OE.
I replaced the regulator and still have power on the blue wire if I disconnect it from the alternator and check the plastic connector.??? There is power on the Regulator VR715 on....

Brown =5.1 volts
Orange =12.8 volts
White or yellow? = 0 volts
Blue =12.8 volts ??????

What is wrong with that? What else can I check? I ohmed out the alternater and that seems all good.
 

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Discussion Starter #7
JimM said:
what does it do if you pull the guages fuse?
Not sure what you mean? I pulled all the fuses under the dash, nothing. Like I said as soon as I pull it from the alt my load goes away. Should there be power on the blue wire feeding the alternator? Someone spliced a plug in so I can't verify what terminal the blue wire should be on the alternator.Is the blue closest to the passanger side?
 

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Discussion Starter #8
JimM said:
the red wire goes straight to the battery and has power all the time...

But the blue and white ones should not. Both pass thru the regulator, and I always forget which is which... but they are labelled on the back of the alternator. The one labelled "F" is the field winding, it turns the alternator on. The other goes to the gen light. Niether should have poiwer with the key off.

Could still be bad regulator, or something wrong in the run circuit of the ignition switch.
The one labeled "F" is the blue wire. Comming out of the regulator there IS power? Does one of the wires turn on the reg when you turn on the switch?
 

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Key off:

Blue wire, alt F, pass side of alt..... 0 v
White wire, Alt R, drivers side........ .06v, call it zero

Alt blue wire goes to top term on reg.
Alt white wire goes to second term on reg
3rd term on reg, red(orange) wire with fusible link, always 12v
4th term on reg, brown wire, 0 v

key on, engine not running
gen light on
alt blue 10.5v

4th term on reg, 12 v
no other changes

engine running

Alt blue F 11-13 volts These 2 vary with RPM, F goes down when rpm goes up
Alt white R 5-10 volts goes up with rpm

reg brown 13 v

While this is all fresh in my mind, here's how it works:

The regulator is the CENTER of this whole charging system thing. It has 4 wires.

Top wire, BLUE, goes to field terminal on alternator. The regulator raises or lowers this voltage to set the charge level. The higher the voltage on the blue wire, the more current the alternator will output at a particular rpm.

Second wire, white, goes to R terminal on alternator. This is a kinda "I am charging" output from the alternator. The more the alternator is putting out, the higher the voltage on this wire is.

Third wire, RED (orange?), is connected to main buss thru a fusible link. Always has 12 volts. The regulator looks at the voltage on this wire to determine how hard the alternator should charge, and varies the voltage on the blue wire accordingly.

Fourth wire, BROWN. This wire goes to the GEN light, then to the guages fuse, then to the ignition switch. This one confuses people. When you turn on your car, the ignition switch puts voltage on this wire, lights the gen light, and tells the regulator to turn on the alternator by energizing the BLUE wire. When the car starts and the alternator is charging, the alternator puts a voltage on the white wire, which tells the regulator to put 12 volts on the BROWN wire. With 12 volts ON BOTH SIDES OF THE GEN LIGHT, the light goes out.

If the alternator stops charging while the engine is running, it removes the voltage from the white wire, which tells the regulator to remove the voltage from the brown wire. With no voltage on the regulator side of the GEN light, but full voltage on the ignition switch side, the GEN light lights, telling you you have a problem.

I think I need to sticky this!

So, mnm99, your problem is the presence of 5.1 volts on the brown wire. This is turning on the alternator, and causing your drain. Tricky part will be tracking it down. I remember from another post that you do not have an msd box, they been known to do this. itsa beetch getting up in the dash, but you may have to...

Does your gen light work?
or
does your car have factory guages?
 

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Discussion Starter #11
Thanks for the long write up. I wish I posted back 5 min ago. I feel real small right now. I got the car 3 weeks ago so it's new to me. After my trouble shooting I found that if your a knuckle head like me don't turn the key all the way to the left, take the key out and go to bed!!!! I feel so stupid. I quess thats why I had power on the brown wire, Duh.. On new cars it won't let you take the key out if you go to acc to the left. It's been a while since I had a older car(20 years). Well thanks for all your help everyone. I'm glad I figured it out. It only cost me $12 for the reg. Thanks again and Goodnight.
 

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well, yes... leaving the key in accessory will keep the alternator turned on and kill your battery... If your gen light worked youda knowed it tho!

Also, the key should NOT come out in the accessory position. Guess your ignition switch is wore out.
 

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Discussion Starter #13
Yea wish it worked! It would have saved me some time!
 

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mnm99 said:
Thanks for the long write up. I wish I posted back 5 min ago. I feel real small right now. I got the car 3 weeks ago so it's new to me. After my trouble shooting I found that if your a knuckle head like me don't turn the key all the way to the left, take the key out and go to bed!!!! I feel so stupid. I quess thats why I had power on the brown wire, Duh.. On new cars it won't let you take the key out if you go to acc to the left. It's been a while since I had a older car(20 years). Well thanks for all your help everyone. I'm glad I figured it out. It only cost me $12 for the reg. Thanks again and Goodnight.
mnm99, Don't feel bad. I have another Knuckle head story to tell you guys.....
One day I walked over to my neighbors house, he was working on his car in the garage trying to locate a tranny leak that he had. He was underneath the car while the car was running with his 8 year old son sitting in the driver's seat at the time. He yelled to his son to turn the car off, so he did. So, I asked him if he spotted the leak and he said it looks like it is coming from one of the cooling lines. So he asked me to start the car again. I turned the key and nothing happened. So I asked if anything was wrong with the ignition and he said no, got up and tried the key himself. Again nothing happened. So I looked underneath the dash to see if any wires had come loose. Everything looked okay, so I asked him if this has happened before and he told me "no" that this was a first. Well he took out the ignition switch and decided to just replace it, so he went to the Auto parts store to get the switch......Well I went home and was going through my parts drawer and came across a Neutral safety switch.........Hummmmmm I wondered. Well, 45 minutes later my neighbor returns home. I asked him what took him so long? He told me he had to go to 5 different Auto stores to find the switch. So I asked him if he had the car in gear and he said "yes" that the car was in gear and his son was stepping on the brake while the car was running. Well it turns out that when the son turned the car off, he forgot to put it back in Park. The thing about it was that the column indicator was broken and it always shows the trans in Park. So neither one of us knew that the transmission was in Drive before his son turned the car off. :D
 

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I have a question about a power drain I am trying to hunt down. If you are testing your system with a test lift between the batt terminal and the cable, with th key off. Can you get a drain from the starter?
I had installed a heat shield around the starter(metal type fabric) If that is touching the pos cable coming in or touching the sylinoid. could this cause a drain?

This is a new car to me so it could be anything
 

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the heat shield wouldn't cause a drain, it would cause a direct short, accompanied by sparks, heat, and possibly fire.

If you want to for sure rule out the starter, disconnect the bat cable pigtail lead from the junction block behind the battery, and connect your meter there.

The drain is often from a bad diode in the alternator, sometimes from the courtesy light, sometimes other stuff. I usually disconnect the alternator first, if it's not gone then pull all the fuses, it will probably go away, then put the fuses back in one at a time till it comes back.
 

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JimM said:
Alt blue F 11-13 volts These 2 vary with RPM, F goes down when rpm goes up

Top wire, BLUE, goes to field terminal on alternator. The regulator raises or lowers this voltage to set the charge level. The higher the voltage on the blue wire, the more current the alternator will output at a particular rpm.
True when taking a reading with a meter. All the regulator does is turn on and off power to the blue wire very rapidly to regulate output.
 
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