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It could be a lot of things. Obviously there is a power drain somewhere. Tracing electrical problems can be challenging and time-consuming. It can take several hours and lots of money to find a 50c problem. A dealer is probably the best option. They only work on Jeeps so they see a lot more of these than an independent garage would so there is a chance that they may have seen your problem before.

I had a persistent power drain on my 2008 Patriot -- my ignition wasn't shutting down when I turned it off. The engine stopped but the ignition was staying on. The clue for me was that my interior lights would not stay on when the doors were open (normally they will stay on for a couple minutes). Turned out there were corroded wires directly below the battery.

Before finding the problem I wrecked two batteries and my alternator died from overwork trying to recharge the dead batteries. It was at 200,000 miles and I debated spending the money. In all it cost $1000+ but my Patriot lasted another 80,000 miles so it was well worth the repair. I sold it to a friend and its still on the road.
 

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Oh, I see you're new. Welcome, Sandra! Please drop over to the newbie threads and introduce yourself to the others. You've got a lot of helpful friends on here. :)
 

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Alternator and battery are good. Still will not hold the charge

According to the service manual, the PCM is what controls charging as opposed to the old school voltage regulator inside the alternator.
There could be wiring issues between the PCM/alternator, PCM/TIPM, or TIPM/Battery causing the problem, or the PCM may be at fault.
Might be best to have a shop hook it up to a scanner to see what's going.

Info from the service manual below:

92180


The PCM (2) receives a voltage input from the generator (6) via the B+ sense
circuit (10) and also a battery sense input (3) from the Gateway (Totally
Integrated Power Module, Integrated Power Module) (4), it then compares the
voltages to the desired voltage programed in the Electronic Voltage Regulator
(EVR) software and if there is a difference it sends a signal to the generator EVR
circuit to increase or decrease output. It uses Pulse Width Modulation (PWM) to
send signals to the generator circuitry to control the amount of output from the
generator. The amount of DC current produced by the generator is controlled by
the EVR circuitry contained within the PCM (2).
 
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