Battery light is NOT coming on at all...alternator not charging.

[92nolatist]

Ok, so maybe this has been covered before, but all I could find were peoples battery lights coming on, mine doesnt illuminate at all whatsoever; not even with the bulb check. And its causing my alternator to not charge.
Ill apologize now for my long post...

So here is how it all started:
I was driving home from work one day and my lights were extremely dim and wipers would barely wipe, right before my driveway, my radio, radar detector and HID headlights were turning on and off because of the such low voltage....however, NO battery light came on, but I didnt think anything of it. I just thought it was the alt. Car sat for about a month because it pissed me off.

As of monday...I got a new alt and I charged my battery fully. Put everything together, even made a heat shield for between the exhaust and alt, cause I thought the heat killed it the first time. Its charging at a beautiful 14.5 volts at idle. Go to take for a test drive and to my dismay, Link is saying 12 volts... and still again, NO battery lights. Bring home and cant find anything wrong, alt plug is plugged in fully and the fuse is good.

I thought well maybe the bulb is bad, swapped with another bulb in the cluster, and unplugged alt then plugged back in. VIOLA! Battery and coolant lights are on with bulb check! And shes charging real nice too. Take for a drive, SAME F*CKING THING HAPPENED!!!!!!!!!!!!!!!!!!!!!!!!! WTF AHHHHHHHHHHHHHHH.

Whats going on with my car guys?? Why does my batt light stop working and thus not turning on my alt? In my FSM, the alt diagram says if the battery light stops working then the alt relay acts as a back up, but it doest seem that way with my car. Could the alt relay be bad and fudging things up? Could it have to do with engine load, seeming that when Im driving its not working? Ive run out of ideas........

Sorry for such a damn long post

 

[blackeagle92]

I had a similar problem on my 1g turned out to be the battery it had a dead cell in it. Does the battery check out ok?

 

[98zx23369]

check the voltage at the fuse box

 

[92nolatist]

Battery checks out fine and the fuse box has all necessary voltage. Im also getting voltage down at the alt plug. What about the alt relay??? I opened it up and its not even a normal relay inside, its like some solid state compenent. Have those ever gone bad on a 1G??

 

[pushen 160]

replace your alt fuse when you take the screw out look to see if the brass needs cleaned and one of the small wires might be grounding

 

[triston2469]

Ok this is going to sound retarded i know but i have had it happen to me in other cars in the past, and I'm really not sure that this will fix the problem. Try putting a new light bulb in the gauge cluster. Like i said i know it sounds retarded but on some charging systems it requires a good bulb to complete the circuit and allow everything to work like it should. I'm not sure that our cars are that way but I have ran into that problem before on other cars and it blew my mind.

 

[Paintballaa5]

luv2rallye can go into more detail on it, but I just had this problem as-well.
There is a alternator "relay" (it acts more like a fuse) on the bracket where the stock boost control solenoid was/is. Your battery light on the dash also serves as a fuse. When one goes out, you have a backup. So if BOTH aren't working, it will not charge.

Try replacing the "relay."
Part #MD128752

You CAN get it from Autozone, I don't remember the PN, but I did manage to find it after some digging. (I work there so I had time to search)

http://www.dsmtuners.com/forums/new...e-charging-system-relay-2g.html#post151081889

Post #5 describes it better than I could.

 

[92nolatist]

It sounds like what you guys are explaining to me is on a 2g, which is different than my 1g. And what was said in that thread that was posted is nothing like what im experiencing.
I've tested the wiring from the battery through the fuse box to the alt and from the instrument cluster to the alt and everything checks out ok. So I'm thinking that it might be the cheap ass no name parts store alternator that I put in there :/ I ordered an OEM reman 90 amp from STM, so ill see if that fixes it.

 

[92nolatist]

Ok, so considering I now have two blown idiot light bulbs, where can I pick up a few? Autozone doesnt stock them... it appears to be part# PC74S. My searches only find a PC74 online....

 

[tektic]

+1 check alternator fuse

 

[92nolatist]

Alt fuse is perfectly fine, but will be getting replaced by a 100amp fuse because I upgraded to a gvr4 90 amp alternator.

 

[98zx23369]

i pulled up your car on prodemand and looked at the wiring diagram, there are two relays and two fuses have you check both?

Engine bay fuses/relays
Fuse 4 30A
Fuse 1 80A federal 100A if canada
Generator relay

Inside fuse box
Fuse 11 10A

Id check those first

 

[92nolatist]

I probably should have noted in the first post that ALL fuses check out OK. I tested the relay yesterday and that too checks out good. Im just waiting on the new OEM alternator and Ill test it and let yall know whats up.
Thanks for your help so far.

 

[Wild Bill]

Ok this is going to sound retarded i know but i have had it happen to me in other cars in the past, and I'm really not sure that this will fix the problem. Try putting a new light bulb in the gauge cluster. Like i said i know it sounds retarded but on some charging systems it requires a good bulb to complete the circuit and allow everything to work like it should. I'm not sure that our cars are that way but I have ran into that problem before on other cars and it blew my mind.

Many charging systems put the alternator energizer wire through the light bulb. When the alternator starts charging positive voltage is equal on both sides of the bulb filament and the light goes out. A lot of manufacturers did it that way to stop backfeed to the ignition system so the engine would shut off when you turn of the key

 

[92nolatist]

UPDATE: So I sourced out two new cluster bulbs and installed them and my OEM reman alternator came in. So I put all that back together yesterday and to my extreme liking, THE CAR IS CHARGING STEADY ONCE AGAIN!!!!!!!!!!!!!!!!!!!! So it was in fact those shiesty ass alternators that I had in there causing my issue.

Word to the wise- NEVER put in an alternator from U.S.A. Industries; total garbage those things are. Always put in OEM. Shes been charging at a nice steady 14.4 volts ever since; with lights on, 13.9-14.1.

Thank you for your help guys.

 

[Tadas]

Hello, guys, I have a similar problem and have no ideas what to do. My car´s alternator is charging a little bit more than 14,8 (about 15,0-15,1), i have checked all fuses and they are fine, but the battery light on dash board doesnt illuminate. I changed alternator relay (md128752), but it didn´t help. Any suggestions?