Battery light in Dash wont go off !98 Corolla - Toyota Nation Forum : Toyota Car and Truck Forums

Felixs10 · 05-20-2011, 03:30 PM

Hello ...Looking for some help . The other day my battery light went on . Checked the voltage and it was overcharging 15.3V at idle. I changed the alt. and no change! Battery also tested good. Any Idea's ??

Thanks.......

militarydave · 05-20-2011, 05:49 PM

new battery

sam333 · 05-20-2011, 06:27 PM

Like dave said... How old is battery?

I have other ideas too ,15.1volts is spec( the correct ) voltage for your alternator, so it may be fine . Did they ( the auto parts store) test your old one?

Your charge light circuit may have a short between the light and your alternator( power coming from the battery is lighting the charge light and grounding before it gets to the alternator).The alternator would still funtion fine, but your charge light would be on.

The L terminal on your alternator goes to your charge light( but goes through a junction connection first) I would look there first.

Felixs10 · 05-20-2011, 10:09 PM

The battery was tested at the auto parts store and tested good.I'm thinking a short or fuse able link problem? Any thoughts?

sam333 · 05-20-2011, 10:38 PM

You have a multimeter , start doing basic testing.

What condition is your charging system in general?

Is there any corrosion , start by checking the output of the alternator (volts and amps)to see if there is anything really wrong.

Like I said 15.1 volts is the correct upper voltage limit for these alternators. Your meter is reading 15.3 and if your meter is a little off....

cdrice · 05-31-2011, 12:16 PM

Try disconnecting the sensor from the brake fluid receptacle and see if the dash light goes off. Worked for me. Now I just leave it disconnected and keep an eye on the fluid level instead of using the sensor. I was told the battery and brake fluid sensors have some paired-up wiring that can cause this phenomena.

Felixs10 · 06-13-2011, 02:12 PM

Thanks Everyone for the replies! Since the car is still drivable and battery is charging ,I havent looked at it yet ,but plan on doing so this weekend.I also noticed that the DLR's stopped working as well as the auto headlights at night. Today the strangest think happened ,I accelerated hard and the Battery light went off,and DLR's came back on! I was very close to my destination and parking in a covered garage and like magic the lights came on as they were suppose too! Later on battery light came on and back to square one. Now I'm convinced that there is a short ! Has this happened to anyone? Do the DLR's,Twilight sentenal and battery light share a ground or relay?

Thanks to all in Advance for any insight....

Felixs10 · 06-13-2011, 02:13 PM

This didn't work , but thanks Cdrice!

Felixs10 · 06-24-2011, 10:16 AM

I started checking the fuses,Relays all around the car.What I found was the DLR Relay on the right front of the car ,next to the headlight was good ,but no voltage going to it to energize the relay. Also the fuses assosiated with the DSr's in the main and secondary fuse boxes under the hood on the left side were all good ,but no voltage passing threw them .The main Headight relay was also good and all the lights function with the headlight switch ( Highs/low beam).
Inside the car the fuse for the Headlights was good and power passing though it.As I said in my earlier posting the DLR's stopped working when my Battery light came on ,so I believe these two problems are connected. Anyone with idea's ??? Please help.... Thanks Felix

Felixs10 · 08-26-2011, 09:21 AM

HI Sam,

I will check voltage at Terminal L off the alt., But you mention a junction ,I also bought the electrical book on my car ( Dealer manual not Hayes) It to mentions this junction ,but where is it? In the wire loom? It makes sence that the problem is what you mention B/C Power to activate the DLR's come off the same junction,I just cant find it. Any ideas were it is? Thanks.....

bimmertt · 09-09-2011, 11:28 PM

Thought I'd let you know that I ran into the same problem several months now with no ill effects other than DRL working/not working sporadically. This happened not too long after I changed out my alternator (from Pepboys) because the original died. Had the battery tested before I changed my alternator and it tested good. Same symptoms as you...battery light always on, sometimes it will go off at idle, or during throttle, DRL working on and off.

Clayton1984 · 09-12-2011, 12:15 AM

Go to an autoparts store and ask if you can test out a new battery to see if the light goes away... just connect it up in the parking lot.

The autoparts store battery tester may not be working correctly or may have very loose parameters for passing.

expertmax · 09-13-2011, 12:42 AM

This is an intermittent problem and will be hard to diagnose.

The first thing I might want to check is the ALT fuse, ALT-S fuse and the DRL fuse. Their "legs" can be broke and when the car shakes, the fuses connects with the pins.

The Junction Connector you are talking about is located behind lower center of dash, taped to harness.

Look for the Junction Box "J10" !

Good luck and keep us up to date with your progress !

Felixs10 · 09-15-2011, 03:17 PM

Thanks for the replys and diagrams everyone. I tried a borrowed new battery .That wasnt it , The Fuses have been pulled ,checked and replaced . I am going to pull apart the center console .The junction appears to be in the lower left hand side of the console.It I dont get voltage at that point ,Im going to run a jumped wire from the Alt terminal to the junction. For the electrical diagram I have there should be 12+ volts at that point with the car running.

Felixs10 · 09-16-2011, 06:06 PM

Hello , Thanks for the Info.This eve I got a chance to try and troubleshoot. I found the connector ( although it was larger and had more than 3 wires coming out of it ! Here is what I found. The voltage I got at terminal L was .6 volts while running, same at the junction.I disconnected the junction with the car running and the battery light went off and DLR's came on !! I cant leave the junction disconnected because the car will not start W/O it connected. I also repeated this by removing the connector at the alt while the car was running.Disconnected the battery light when off and DLR's turned on.
What should the voltage be at Terminal L with the car running?How come the battery light goes off with it disconnected? Looking at the wiring diagram of the charging circuit shows that voltage passes from the battery to the charging light in the dash ,then to terminal L then to the Alt. If this is correct is terminal L simply an on off ground?
Lastly what would your thoughts be on running a jumper from terminal L at the alt. to the junction under the dash and isolate the circuit by cutting the factory wire coming out of terminal L ?

Thanks Felix