Charging Light Issues, HELP

Need input on a problem with charging light issue. Replaced battery, and been through two rebuilt alternators, still have charging light on. Belt seems to be fine that is the only thing left to change. Any input or ideas? HELP! At idle output is about 13.5 13.7 with lights and air on.

 

Check the plug that goes into the alternator for corrosion, they grey wire should have output voltage with engine running. It is not sending voltage to the light to turn it off. If the pin is not output voltage the ic regulator has failed

 

I will give it a try, what is IC regulator? Thanks

 

Voltage regulator in the alternator

 

Would I still get an indication if led shorted out?

 

After I changed Alt. (rebuilt) light blinks at start up and then stays solid.

 

Still have problem , looking for input or suggestions. This light is really bugging me starts and runs fine. Thanks

 

Have you checked the grey wire for voltage that is in the small harness on the alt?

 

No, just checked voltage at battery, running and off. I will give that a try this afternoon . Thanks

 

The voltage that you are mentioning while running, under load, is quite acceptable. Perhaps there is a problem in the signal wire to the ECU?

 

WHERE IS MAX??!!!

VOLTAGE DROPS!



Clean your grounds too.

 

I was double checking the wiring diagram, and I knew that the alternator sent a signal to the ECU. I was mixing it up with the GM vehicles where the ECU sends a class 2 data information signal to the IPC telling it to illuminate the Charge indicator. Looking now at the wiring diagram for a 2006 I see that the grey wire at the alternator is the ground control for the charge light. (doesn't connect to the battery) Also the Body control computer can also light up the charge indicator, so there is a possibility there.

The charge light does not come on with a difference of 2 volts between battery and alternator however. Since the alternator is connected directly to the positive circuit, there would be no way to tell. The charge indicator comes on when there is a ground on the grey wire from either the BCM, or alternator. The alternator's internal regulator will ground the grey wire if positive voltage is below the threshold minimum of about 13 volts or exceeds 18 volts. This is why your charge light is on when the key is turned on, and the engine is not running.

 

Thanks for all the suggestions and advice , going through them one at a time. Some of them are above my pay grade but I will keep you all posted on progress. Again thanks for informative input!

 

It's all good. I have missed things myself. I always say there are no perfect, trained technicians, only technicians in training. The day I have nothing more to learn on cars and trucks is the day that they stop changing them.

 

Well......... checked plug on alt. (Grey wire) checked connection on dash charging light, hard to get to. Cleaned terminal posts and grounds. still have charging light but now have new problem! Daytime running lights do not work. Turn signals and emergency lights work fine. I am thinking this is connected to charging light. I had a new dtrl relay and changed it but it did not help. I cannot find any fuse listed dtrl . Anybody have any clues? Thanks

 

Update... Replaced alternator, serpentine belt, positive batt. connector checked grounds ( from alt. to frame, from engine to harness) cleaned and checked plug to alternator all connections fine. 12.7 volts with engine off. 13.8 running with lights and air on. Charging light still on, now DTRL will not work most of the time. sometimes they come on. Flashers and turn signals work normal. Also checked connections to charge light the best I could, hard to access. Anybody got any advice? Thanks again for all help so far this thing is driving me crazy!

 

I hate to say it, but at this point perhaps the best move would be to take it to a dealer to get it checked out. Then you can choose what to do or not do after that.

 

Actually, last Tuesday took it to one of the Toyota dealerships in town for a 59.00 diagnostics test and they could not find an issue but said 80.00 an hour they would dig deeper but could not tell me how many hours it would take. I guess I am more stubborn or cheap to let this whip me. I guess I should have said us since the best advice I have gotten has came from this site. Thanks for all the input if anyone can think of anything else please post. I will report back later when I whip this thing. Thanks again

 

Still searching for help! Anyone have any new ideas or suggestions?

 

Still have problem, hate to pay 80 dollars an hour for fishing trip! LOL Any ideas greatly appreciated.