If the battery light is on, it usually means that the alternator has a problem. Have the alternator checked at a local auto parts retailer. If one or more of the diodes are bad, your battery charge will be affected.
check the distributer cap
Connected to the exhaust of the Celica with one in front of the catalytic converter and one behind it. There are two.
My 1990 Toyota Celica Idle is too high... What seems to be the problem?
the answer is if that happens u can check the 100amp (blue) alternator fuse next to the battery...
To find the transmission dip stick on the 1986 Toyota Celica, open the hood of the car and locate the battery. Near the battery, you'll see the left front part of the engine compartment. That is where you'll find the dipstick.
Under the hood (passenger side) attached to battery brace
Directly above the battery, right side of the engine compartment. It's inside the black air-filter-box. At least it's like that on my Celica.
You can, but you'd better put a fuse in-line, next to the positive battery post, otherwise when it rubs through, (it will) you will have a red-hot wire that will damage one of many things, including your battery or setting the whole engine compartment on fire. Better that you find out why you are having the problem that makes you need this fix. I suspect you are having a problem getting the battery to charge. Better check: your battery...the battery cables, the alternator fuse, the fuse links under the fuse box and MOST importantly, all the grounds to the body. (There is one next to the fender by the battery, one on the passenger side connecting the engine to the strut tower (it unplugs). I added a ground to the firewall and connected it to the fuel rail. Without proper ground you can have engine operation problems and charging problems. Good luck! Auntetr
Check all fuses
Try changing the fusable link located near the battery I hope this helps.
yu gotta program it
You could have as simple a problem as a ground not getting a good connection, a corroded terminal(or wire) on the wire from the alternator to the battery, or maybe the plug in that goes into the voltage regulator is bad. I would first take an ohm meter and see if you're getting all the power from the alternator to the battery. One other thing might be a short in the computer. Good Luck!