Electrical guru's please help me with charging system problems!!!!

[fastimes69]

Ok, I'm having some trouble with my charging system. I have a 130 amp alternator on my car. I checked the alternator, and battery at the local Autozone and they are both ok. The alternator was bench tested and works good. Still the car wont charge. I did a search and got some wiring diagrams as well . The black and orange wire that runs from the solenoid to the alternator is good and checked voltage. It should have 12 volts but since it is not charging it reads only 11.6 volts then slowly drops. The black and white wire that has the female and connects to the back does not have enough voltage going to it. I was told it should also read 12 volts and has way less. I tried running a wire from the battery to that wire to see if it would help but it still did not charge. Does anybody know what else I could check or what it could be ? I've just about had it, I can't figure it out, It had been working fine until recently !!Thanks for your help.

 

[RacEoHolic330]

make sure that you check all your grounds and connections to the regualtor. Are you sure that your regulator is working okay? Does the AMP light come on in the dash cluster?

 

[jrichker]

See http://www.geocities.com/smithmonte/Auto/3G_130A_Alternator_Upgrade.htm for correct 3G wiring. If yours is still using the black/orange wires, it is wired wrong.

See http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif for what the orginal wiring was supposed to look like. Note that the yellow/white wire has a fuse link in it that feeds the built in voltage regulator for the 3G alternator.

 

[fastimes69]

.It already had this wiring, the one used for the alternator to the solenoid just happened to be black and orange as well. It can't be wired wrong because I've had this setup for over 3 years and it always worked fine.Any other suggestions?

 

[BRADY5.0]

the pully's were causing the problem in my 92--as soon as i took them off and put the stock back on--no problems!!

 

[HISSIN50]

how was the charging system tested (on a bench or in the car)? if you have no/low output, that should have come up when you did the in-car test, if that is the route you went.

is your alt self exciting? as JR said, the yellow/white wire has a fusible link - is the link alright?

good luck.

 

[fastimes69]

It was tested both ways, in car and bench. It's not the pullies cuz its had them on for a few years. The link is ok too.

 

[HISSIN50]

sorry, i just re-read your first post and saw that you had bench tested it. my bad.

im confused how you can be reading discharging while the tests (esp the in-car) test showed you were alright. did the guy tell you what it said your output was?

im not doubting you at all - im easily confused and trying to help.

good luck.

 

[Idwitheld-1`]

Lets get back to basics here.

1. with car engine off...should have about 12 vdc across the bat. terminals.
2. with car running at 2K rpm, should have 14.7 vdc across battery terminals.

In 2 = no, then check the white connector with black/orange wire...the terminal may be burned or chared. Back probe the black/orange wire at the alt (referenced to battery ground stud.). FYI you should NOT be using the stock wire on a 130 amp alt. This is a recipe for a blown alt or a car fire (or both). If 14.7 vdc, check for a open wire on the orange/black wires. If nothing, check the ground wires for an open.

amnother method:
Get a clamp on meter. clamp it to the black.orange alt wire. If current is present then your connected to the battery (car load). Next move the calmp on meter to the battery terminal + wire. If the current reading is greater than the alt wire, your running on your battery (and not the alt). Try the same test at 2K rpm. IF same results the alt is low output.

Hissin50..I'm back on the web! (down but not out)

 

[fastimes69]

Well I looked through Autozones website and they had some good info on trouble shooting.One was to disconnect the positive battery cable from the battery and connect the ground wire on a test light to the disconnected positive battery cable. Touch the probe end of the test light to the positive battery post. The test light should not light. If the test light does light, there is a short or open circuit on the vehicle. Mine checked out ok.The next test was to disconnect the voltage regulator wiring harness connector at the voltage regulator. Turn on the ignition key. Connect the wire on a test light to a good ground (engine bolt). Touch the probe end of a test light to the ignition wire connector into the voltage regulator wiring connector. This wire corresponds to the I terminal on the regulator. If the test light goes on, the charging system warning light circuit is complete. If the test light does not come on and the warning light on the instrument panel is on, either the resistor wire, which is parallel with the warning light, or the wiring to the voltage regulator, is defective. If the test light does not come on and the warning light is not on, either the bulb is defective or the power supply wire from the battery through the ignition switch to the bulb has an open circuit.Still my car checked out ok!!!Any other suggestions?

 

[Idwitheld-1`]

Well I looked through Autozones website and they had some good info on trouble shooting.One was to disconnect the positive battery cable from the battery and connect the ground wire on a test light to the disconnected positive battery cable. Touch the probe end of the test light to the positive battery post. The test light should not light. If the test light does light, there is a short or open circuit on the vehicle. Mine checked out ok.The next test was to disconnect the voltage regulator wiring harness connector at the voltage regulator. Turn on the ignition key. Connect the wire on a test light to a good ground (engine bolt). Touch the probe end of a test light to the ignition wire connector into the voltage regulator wiring connector. This wire corresponds to the I terminal on the regulator. If the test light goes on, the charging system warning light circuit is complete. If the test light does not come on and the warning light on the instrument panel is on, either the resistor wire, which is parallel with the warning light, or the wiring to the voltage regulator, is defective. If the test light does not come on and the warning light is not on, either the bulb is defective or the power supply wire from the battery through the ignition switch to the bulb has an open circuit.Still my car checked out ok!!!Any other suggestions?

A test light will only take you so far. You need a Digital Volt Meter (DVM) to help isolate the problem. Where are we at with the test above?

What is the voltage at the batt at 2k RPM?

 

[jrichker]

Look for power on the Yellow/White wire on the alternator. No 12 volts means that the 14 gauge fuse link has opened up. This circuit supplies power to the alternator regulator.

See http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif for more information.

 

[fastimes69]

Well I have tested it myself with a volt meter. At 2k or above it still only read 11.6 volts or so. It never goes up. Ok next I'll look at the yellow and white wire.If it has power, how many volts should it read? If it does not have power, what would cause that? Thanks!!!!

 

[HISSIN50]

i would think it should have 12 volts. make sure to check each side of the fusible link for 12 volts. check the condition of the link too (is it all stretchy feeling, like it has nothing inside it, etc).

JR will know more about that wire - i just remember that it is for the regulator and to keep it when doin a 3G.

good luck.

 

[jrichker]

Well I have tested it myself with a volt meter. At 2k or above it still only read 11.6 volts or so. It never goes up. Ok next I'll look at the yellow and white wire.If it has power, how many volts should it read? If it does not have power, what would cause that? Thanks!!!!

The yellow wire should have battery voltage, whatever that may be. It connects to the battery with a fuse link to protect the circuit.

 

[fastimes69]

Ok, I'll look in to that later today and see what happens. Thanks

 

[fastimes69]

OK, I checked the yellow and white wire but it does not have power. My setup has a one wire hook up that runs to the solenoid, then a three wire connector for the voltage regulator, and a black and white wire alone with a female connector.

 

[jrichker]

If the yellow wire connects to the alternator, it must have power for the alternator to work. It is the power feed for the built in voltage regulator.

 

[fastimes69]

Well I finally found the problem!!I traced the yellow and white wire from the alternator all the way up to the solenoid. What I found was that somewhere under the battery tray, the wire was cut and the rest of it all the way up to the solenoid was black. It came loose where it was taped up so thats why it was not getting power and charging. I fixed it with an inline fuse and works great again. Thanks to the guys who helped me through this, ya'll were a big help. If I knew you all personally I'd buy you all a 6 pack of beer or something lol . Thanks again and stay cool. Later