amp gauge warning light

[rbuhler]

When ignition is off the warning light on the amp gauge stays lit up anybody know why

[opelspyder]

Check to see if a power wire to the dash is not been placed into the wrong tab of the fuse box. Have you done any wiring work, or changing anything??? The wire that powers the gauges feeds the amp gauge light. It receives its ground from the (blue/white??) wire of the voltage regulator. So for some reason the power supply is on at that time. Is the temp gauge workingas well? I think the gauges would be working as well

[opelspyder]

Oh another thought...if memory serves me well, the wire that may be on the hot all the time fuse instead of an ignition on fuse would be (black/red) in color. This circuit powers all the gauges. I would imagine if the circuit is hot, then the gas gauge or the temp oil gauges would show they are working too

[timemachine]

I am not a GT wiring expert but I have seen this happen a few times in other cars, including one of my Mantas. If you haven't been moving wires around, I wouldn't worry about that stuff beyond a simple inspection. It's not your ignition switch because a single wire powers all the accessories including the oil light, which isn't coming on.

What happens is that a leaky diode or cap allows B+ from your alternator to flow back through the light and it then finds a partial ground through the accessory circuit. Even if your car charges okay, and I assume it does, it might well be a faulty voltage regulator.

Try removing the connector from your voltage regulator (a three wire plug from the alternator) and see if that turns the light off. If it does, it is very possible that your regulator has gone bad. I'd still recommend plugging in a spare or borrowed regulator before buying a new one, but I have seen this before.

Jim

[baz]

i would second reg pack too , back feed from alt is most common reason i can think of

[rbuhler]

I just purchased this 3 GT's and have done no wiring I will try using a spare regulator from another GT I have tonight

[rbuhler]

I uplugged regulater light stays on, I'll try power wire from gauge and see if it is connected staight to positive live circuit

[timemachine]

Again, I don't have a GT diagram but on most cars I have seen, the ammeter GAUGE is always on, key or no key, connected in the battery line to the alternator. Big battery lead goes to starter, smaller lead goes from starter to alternator B+. You could test this by turning your lights on while the car is off to see if the ammeter shows discharge.

The alternator idiot LIGHT is supposed to show battery discharge only when the ignition is ON (via the regulator). When the ignition is on there should be 12V+ at one side of the bulb whether the car is running or not. The ground that causes the bulb to light should normally come from the regulator.

BTW, does the car seem to charge and hold a charge okay? I suppose a bad diode in the diode pack inside the generator might also cause this problem. You could disconnect the red wire on the back of the alternator to check, and also make sure you have a good ground wire from the alternator case to engine block in case the field is leaking. (Even though the alternator bolts to the block, it has rubber bushings that insulate it.)

Don't want to overcomplicate, just trying to help.

Jim

[rbuhler]

after checking everything out from these posts I found not only is the light on the alt. gauge on, but I have power to my wholeright side fuse panel when ignition is off and my voltage regulator gets warm and in the morning my battery is dead. After checking everything out I found if I disconnect the red wire #10 from the alternator the light goes out and the fuse panel goes dead with key off. What am I missing is this wire in the wrong spot on tne fuse panel or is wire on wrong place on alternator there are 2 spots on diode support

[timemachine]

Originally Posted by rbuhler after checking everything out from these posts I found not only is the light on the alt. gauge on, but I have power to my wholeright side fuse panel when ignition is off and my voltage regulator gets warm and in the morning my battery is dead. After checking everything out I found if I disconnect the red wire #10 from the alternator the light goes out and the fuse panel goes dead with key off. What am I missing is this wire in the wrong spot on tne fuse panel or is wire on wrong place on alternator there are 2 spots on diode support

Now we are getting somewhere. There are nine diodes in the generator, three of which provide an isolated power source to your regulator. That could be your problem. Take out the alternator and have it tested. Most shops, including advanced auto parts do this for free. There's probably an automotive electric store in your area that can fix anything and they're usually pretty reasonable. (I am assuming the regulator has been isolated and is not the problem.)

The two bolts on the back of the alternator do the same thing. The B+ from the battery is usually connected to the one nearest the engine to keep things tidy.

Two or three of your fuses will always read 12V to ground so your brake lights, dome light and emergency flashers always work.

Jim

[jlthunder]

Originally Posted by timemachine Now Two or three of your fuses will always read 12V to ground so your brake lights, dome light and emergency flashers always work. Jim

Jim your advise is great, but one small correction. The brake lights are on the key. When you turn the engine off, the brake lights don't work anymore.

Yeah, I know, I'm being picky.

[rbuhler]

the regulator has been tested its OK I will take off the alternator and swop it with a spare and get this one checked out. And yes no brakes key off.
thanks for the help

[wrench459]

Just for grins whats the AC ripple under full load?

[jlthunder]

Originally Posted by rbuhler swop it

New term from our friends up North

[rbuhler]

well I finally had time to swop out the alternators and bingo everythink works fine.Now that I have it running off to tackle the brakes, to get it stopping.