So yesterday it was around 7-35 degrees for a high and i being dumb and running late locked my keys in the car. so from 8am to 8pm the jeep sat in the parking lot at work and when i finally get back into it and start it up the check engine light comes on. and the instrument panel was really dim and all other items powered by cigarette lighter were off. i checked the volts gauge and it was near the red for discharged, so i revved it a little and then the instrument panel and was bright and cig powered stuff came on.

So my codes were 12 and 54.
12 i thought was for batt being disconnected??
54 means distributor sync sensor, right?

no with these codes shouldnt the jeep be running poorly and stalling? my jeep is running fine, has good pickup, and typical bad gas mileage.

So whats the deal here? any ideas???

FYI, 95 Cherokee Country 4.0, AW4. 184K miles

 

12 batt disconnected last 50 key cycles and sure it was no 55 end of test

 

code 54 xj would not start

 

12 and 55.
If your alternator was wet and then it sat for a while it might of glazed over the brushes with ice. Revving it got rid of it.

 

well i double checked the computer codes and i may have been wrong its comming up only as a code 41

 

you should be getting a 55 along with the 41. 55 is "end of codes"
http://www.allpar.com/fix/codes/faults/code-41.html

 

well the alternator decided to stop working all together on my way to work this morning. and of course its 20 degrees out barely got the jeep back home, with no heat and no pretty much anything electrical. the gauge was pegged at 9 and everytime i hit my brakes the speedo and tach would bounc around like they were on crack. so now i gotta replace an alternator in below freezing weather, this sucks!