this is on a 96 cavalier 5spd 2.2.
When i was driving up to the mountains one day i noticed the battery light flicker on and off occasionally and kind of randomly. the next day i drove the car into town it still did the flicker but it slowly got worse. the ABS light and the brake light turned on. while sitting at a stop light the charge light was on and after driving away from it the light turned back off. so as im driving more and more lights come on the dash and even the spedo freaks out with all the other gauges. well anyways in a frantic limp to autozone the car died as soon as i pulled into the parking space. no juice left in the batt. i pull the alternator take it inside and it tested fine passed everything. (the battery was replaced about a week previous to this due to a bad battery not holding a charge) so i was stumped got a jump and after a couple minutes it would die again. pull the batt cables off and it would die. pretty much seems like the alt isnt working but it passed the test. i started tearing wiring apart looking for the problem but cant find it.
this really has me stumped, and i dont have access to a multimeter to probe out the wires right now.
Try to run a new wire from the alt directly to the battery, as if you were upgrading the big 3. I would trickle charge the battery first and see if that helps.
Sold 6/30/06.
NEVER take your battery cables off while the car is running. taking them off can send an electrical shock to your ECM or BCM and make things worse. if you think your alternator is bad then take it off (its a 30 minute job to replace an alternator) and take it to Checker auto, Advance auto, NAPA, or virtually any other auto parts store and the should test it for free.
He never said he took the cables off while it was running. He also said he already removed his alternator, took it to autozone, and it tested fine.
Sold 6/30/06.
I would start looking at wiring, but first is your belt tension good on the alternator pulley, not to loose or to tight?
- 2004 Cavalier - 124k, owned since new
96 cav wrote:-=Shadow=- wrote:pull the batt cables off and it would die. pretty much seems like the alt isnt working but it passed the test.
david norris wrote:He never said he took the cables off while it was running. He also said he already removed his alternator, took it to autozone, and it tested fine.
Well yes he did.
yes i did take it off and yes i know the hazard of doing it. i was kinda stranded and needed to trace the sorce with what i had at the time.
and i tried jumping the alt wire to the battery, i gave the batt a charge started it and then hooked the jumper cables to the post on the alt and the other side to the batt and no difference. as far as i can tell with what i tried it seems like the alt is bad but it passed the test.
anyone have ideas? im really stumped on this. thx.
If, as you say, the Alternator tested OK I would then check:-
1. The Negative Battery cable Ground connection at the chassis and/or engine block--actually disconnect the cable and check the cable end and the contact point on the engine/chassis is shiny clean then reconnect.
2. My car(93 2.2) uses the large terminal on the Starter Solenoid as a junction block connection for the cable from the Alternator Batt terminal and it's Fusible link and a second cable to connect to the Battery Positive----are all the connections on the Starter clean and tight?
3. The Rotor winding of the Alternator has to be energised with +12 volts from the Battery (In my '93 2.2 this is the Gauges fuse--switched on by the ignition switch)----this obviously happened when it was tested---I am wondering if you have no 12 volts to the rotor in the car.
Also, later models (than mine) have a charging system where the PCM switches the Alternator on and controls the output---perhaps someone with a 1996 Shop manual/wiring diagram could help here.
Just some ideas
Alont
i have the same problem, all my wireing is good, replaced the silenoid, alternator is good, battery is good......yet my batt light\abs light comes on...i was thinking that the pulley isn't moving fast enough to create enough energy from the alternator???...i took it to 2 mechanic professionals and they both couldn't figure it out...yet i think its the theory that i stated..??? any other ideas lol! thats the only reason i havn't drove my j-body for 5 months is cuz the charging system.. :[
alont wrote:If, as you say, the Alternator tested OK I would then check:-
1. The Negative Battery cable Ground connection at the chassis and/or engine block--actually disconnect the cable and check the cable end and the contact point on the engine/chassis is shiny clean then reconnect.
2. My car(93 2.2) uses the large terminal on the Starter Solenoid as a junction block connection for the cable from the Alternator Batt terminal and it's Fusible link and a second cable to connect to the Battery Positive----are all the connections on the Starter clean and tight?
3. The Rotor winding of the Alternator has to be energised with +12 volts from the Battery (In my '93 2.2 this is the Gauges fuse--switched on by the ignition switch)----this obviously happened when it was tested---I am wondering if you have no 12 volts to the rotor in the car.
Also, later models (than mine) have a charging system where the PCM switches the Alternator on and controls the output---perhaps someone with a 1996 Shop manual/wiring diagram could help here.
Just some ideas
Alont
1. good point, ill have to check the main grounds. the only thing would be that the alt is self grounding and im sure the the block is ground more than just at the main connection from the batt. there has got to be a chassis-block ground somewhere or other grounds that would suffice. if i can just get my hands on a multimeter this would go better.
2. i checked that allready. i actually cut out and bypassed the fusible link because i thought it could have went. also jumping the main pole to the batt should have bypassed that whole circut and showed some changing signs.
3. another good point, if the pcm isnt controlling the voltage regulator then it would be like no alt. how would i go about testing this without a multi meter?
Quote:
i have the same problem, all my wireing is good, replaced the silenoid, alternator is good, battery is good......yet my batt light\abs light comes on...i was thinking that the pulley isn't moving fast enough to create enough energy from the alternator???...i took it to 2 mechanic professionals and they both couldn't figure it out...yet i think its the theory that i stated..??? any other ideas lol! thats the only reason i havn't drove my j-body for 5 months is cuz the charging system.. :[
95' 2.2L OHV stripped totaly, just frame engine and pass+driver seat haaa =D
the only thing with that is the idle is the same as it allways was. im running stock pullies so it should be spinning plenty fast enough. plus you would see a significant difference when the engine is reved. for me that just drains the batt faster til it is dead.
i just dont know where to start with this
Quote:
how would i go about testing this without a multi meter?
Not really possible... might be if you have a volt gauge?
Walmart has a DMM for about $15
Courtesy of KARDAIN and NY j bodies
The PCM wiring is
in C1-27 on the PCM to Terminal C on the Alternator---this would give you Genr Lamp ON and no Rotor current--no output--If there is no +12 volts to pin C.
The PCM switches this +12 volts ON and OFF---more On than OFF when Battery is low and vice versa.
You could try temporarily suppyling +12 volts to Pin C on the Alternator connector and see if you have a charge.
1. * 12129025
2. * 32-Way F Micro-Pack 100 Series (Black)
Pin Wire Color Circuit No. Function Component Connector Cavity DTC(s) Affected
C1-27 GRY 23 Generator F Field Signal Gen Term C -- GEN Lamp ON
Possible Symptoms From a Faulty Circuit -------GEN Lamp ON
Alont
alont wrote:Courtesy of KARDAIN and NY j bodies
The PCM wiring isin C1-27 on the PCM to Terminal C on the Alternator---this would give you Genr Lamp ON and no Rotor current--no output--If there is no +12 volts to pin C.
The PCM switches this +12 volts ON and OFF---more On than OFF when Battery is low and vice versa.
You could try temporarily suppyling +12 volts to Pin C on the Alternator connector and see if you have a charge.
1. * 12129025
2. * 32-Way F Micro-Pack 100 Series (Black)
Pin Wire Color Circuit No. Function Component Connector Cavity DTC(s) Affected
C1-27 GRY 23 Generator F Field Signal Gen Term C -- GEN Lamp ON
Possible Symptoms From a Faulty Circuit -------GEN Lamp ON
Alont
Very helpful thx, pretty much that circut seems the most likely for these symptoms because that would mean the alternator is good but the pcm just isnt turning it on.
I did manage to borrow a multimeter so i can get somewhere on it.
What do the onther connections on the alternator do? is it a ground, and the pcm wire? i havent look at it in a bit but i thought the plug is a 4 pin with only 2 wires. anyways if i end up finding something then ill post what i find. fingers crossed its just a simple broken wire in an easy spot
^^^ how u fix wut alont said?? or check it lol
Jay wrote:^^^ how u fix wut alont said?? or check it lol
well you know the wires that are on the plug on the alternator. there is the plastic clip that the pcm supplies 12v to to essentially "turn on" the alternator. im guessing the other wire is a ground for the voltage regulator or another wire to the pcm sending info to it.
So i guess if these wires are broken or not making a good connection the pcm cant turn the alt on. the alternator qwould still be good its just not working because its not being told to. om actually going to go outside and throw the meter on the wires and see whats going on.
well.... im stumped. i went out tested everything (i dont know the quality of the meter so the readings were weird) the alt was putting out 23v, weird much, but anyways pin c on the connector read out at 7.3v the batt was bouncing between 13-22v on the terminals, i tested the main ground to the batt from the terminal on the trans and it was making a good connection. i ran the car for about 45 mins and no batt light no nothing it seemed normal and all i did was unplug the connector on the alt and test it put it back on tested everything and drove it off. no major changes or nothing.
so kinda weird because the problem went away with it just sitting? maybe it was a glitch in the pcm and it needed to sit and do a cold boot to reset itself?
wow wish mine would do that rofl.
I think it was disconnecting and reconnecting that Alternator connector fixed an iffy contact------but great that it's working anyway.
The 7.3 volts reading is correct, on some systems, ie it's half of the final output 14.6 volts.
Will do some more research when someone is brave enough to climb the tower down Toronto way and fix the Broadband, a week now without it
Alont
its doing it again!!!! ugh
worked for a couple days and now its back to the same thing. i just caught it earlyer this time and had teh meter to pull some readings off the wires.
so far i think its somewhere in the pcm wiring. it seems as i can pull the plug off it will read 7-9v (pin-c) and ill put it on the altornator. the light will go off and it will be fine. i shut the hood and get in the car and the light is back on again. repeat and same results. i tried backprobing the pins and cant get a reading off them. but the alt was charging at 19.8v and all of the charging system read out at that (bat and misc other places like starter terminal etc.)
im thinking it might be a bad connection in the plastic clip on the alt. im going to try and go to the junkyard and clip some wires and find out if replacing the plug works. if not ill run new wire to the pcm. hope this works, ill update as i find out incase alnot needs it.
try it and reply back and tell me how its working..i could really use an update :]
Jay wrote:try it and reply back and tell me how its working..i could really use an update :]
ok will do jay.
ive got to go check out an mkii supra today that i might buy but after that im going to see if i can shoot by the junkyard for some wires.
ok, so i did a few things. i replaced the plug on the alternator, i replaced the fusible link from the starter, i cleaned the main grounds on the battery tray and the transmissin (battery tray is really rusted and coroded) and i ran a peice of wire from the battery tray connection to the batt terminal to the radiator support.
after doing all of this i started it up and drove it around and no light came on at all. so it seems as though it is working properly now. there probly was a bad connection in the plug. but ill keep an eye on it to see if the problem comes back.
