Alternator or computer problem ?
 

Hello,
I have a strange problem with the alternator or computer or wiring... Every day, for the past three months, it has happened in the same way:
When I start the engine in the morning to go to work, everything works fine (the alternator is charging, the needle stays in the middle, etc.)...
When I start it again at lunch time, it gives me a check engine light; I read the code and it is 41 (problem in the inductor circuit of the alternator - open or gounded). At the same time, the alternator seems not to be charging (the indicator is in the left part of the dial, almost in the red). Usually after a few seconds or minutes or driving, the indicator indicates it is charging again.
At this point, if I stop the engine and start again within a few minutes, everyting is working again. If I park the car for about for a longer time, the problem happens again when I start it...

The problem first appeared during the rainy season (I live in Mexico) and seems to be mor frequent when the weather is wet. I tried to clean the cables and insulator of the inductor circuit, but it didn't help. I checked the groundig of the engine and it is fine (the previous owner also seems to have installed an additional cable to ground the battery). Since I thought the alternator could be dirty I blew some compressed air into it, things seemed to improve for a couple of days and the problem happened again...

Last month, I brought the car to an electrician and he told me he checked the alternator and it was fine (I also checked the voltage when the alternator is charging, and it is fine). He cleaned the started instead (I also had intermittent problems with the starter, maybe once every 50 times it wouldnt start). But that didn't fix the problem.

Now this behaviour is getting more frequent (although it is now the dry season) and I'm worried this will leave me stranded some night...

Any idea what could be happening, and where the problem would be: alternator, wiring, computer ? I wouldn't like to change something if it is not the problem...

Re: Alternator or computer problem ?
 

hi, one week ago my cherokee 1996, 4.0L, 4x4 had same problem. 44 and 47 fault code. I solved: change de carbons inside the alternator (Denso 90amp), cleaned all ground wiring (engine block and fender).

Re: Alternator or computer problem ?
 

Thanks Latitud 39 !
That was actually the reason: three weeks ago the alternator went completely and I had to bring it again to the mechanics; he finally changed the carbons and now everything is OK again... So much hassle for such a cheap thing...