use2b50guy

Thanks, I checked the ckt. Got batt back up power with the key off. I went to advance auto this time to use their tester, instead of going back to auto zone, they tell me that any codes related to the cel in the 1000's are manufacturer specific and can only be cleared by the dealer. Does this sound correct to anyone? Leads me to believe the ecu needs to be reflashed. Ive tried repeatedly to clear it myself by pulling the fuses and disconnecting battery, but no luck.

First thing to do would be to put a fluke on the battery terminals with the car running to see if you have around 14.5 volts. Do this preferrably when the batt light comes on. If you getting 14.5 volts, then the alternator is working. YOu should have 12.5 without the car running. If you dont, your batt toast.

So no one else has ever has a cel come on right after changing out a dead battery? Car runs fine, and I got voltage at the battery back up ecu pin. Not sure what else it could be. How often to the ecu's go bad?

Has anyone ever got a check engine light after changing out a dying battery for a new one? I just changed the battery in my 94 es300 and now the check engine light is on. The car has 97k original miles on it. I disonnected the battery over night again, tried clearing out the code with the obd II scan tool at autozone this morn, and the code come right back. It sounds like a KAL pwr feed for the engine ecu. If anyones had a similiar problem what did you do to fix it? I know if I take it to the lexus dealer theyll want to change out the ecu for some outrageous price that wouldnt fix it anyways. Thanks...