Electrical problems with my 2000 LX 2.3L. SRS, ABS, MIL, door/trunk/brake lamp, battery indicators started coming on in the evening. In the morning the battery was completely dead, no relay clicks or anything. Jumped it, as soon as I started it both rear windows went down and stopped working. Replaced both window fuses, both blew again when key was turned to ign (II). Car running so I dropped it off at a local guy who has been okay for diagnostics and complex stuff before. Called back, alternator’s voltage regulator bad, and the car’s voltage spiked. His mentioned having possibly fried the ICU? I can’t find any good info on this online, and need to know more about these units. I have a shop manual on the way to help figure out the diagnostics on this and have some other options lined up since the estimate at the shop obviously isn’t feasible.

Anyone who can give some info on the ICU or which electronic components I can expect to be fried from this voltage spike and diagnostic tips for checking out the system. I’m getting the alternator tomorrow and will have the car back Monday morning. Thanks.

 

yea you can easily expect for the computer to be fried as well as a bunch of relays, your headlights, your dash. os many things can blow with a bad regulator. first.....put a new alternator in, then see what other problems you have after replacing any bad fuses.


lightshow

 

Okay, this is the current situation. I replaced the alternator with a high quality rebuild. The car is running fine and the MIL/CEL is not lit. No other indicator lights are coming on, which should indicate no ICU failure (my wiring diagram refers to these as multiplex units).

I replaced the blown rear power window fuses (20A). Turning the key to II blows them instantly. I then removed one of the rear door panels and accessed the power window motor and switch wiring. With the key at II and the switch connected, there was no motor response. With the switch disconnected, I was able to confirm 12V at one terminal of the switch connector. I then jumped the 12V directly to both terminals of the power window motor and there was no response.

I need to know the nature of the power window circuit. With the 20A fuse blown, I am assuming that the power window motor is still grounded. If this is the case, and I have no response from the motor, can I safely assume the motor is blown. If the motor is blown, is there any way it will blow the fuse when the key goes to II. Anyone heard of a blown window motor blowing the fuse when the key goes to II? Any info is appreciated.

 

yes if the motor is blown its like touching both ends of your battery together. it will toast a fuse immediately. if you give the motor power with no response it is probably blown. congrats on the computer still being good.