Battery Light
12-13-2008, 11:52 PM
#11
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Having a similar prob:
JK starts no problem, but lights alternator light for a few minutes, then check engine light stays on.
Perhaps low batt. charge? Alternator malfunction? some amperage draw while Jeep off?
If I discover cause, will report. C
JK starts no problem, but lights alternator light for a few minutes, then check engine light stays on.
Perhaps low batt. charge? Alternator malfunction? some amperage draw while Jeep off?
If I discover cause, will report. C
01-06-2009, 09:51 AM
#12
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It happened to me yesterday. On my commute to work the battery light came on and the accessories started to lose power (radio, fog lights, wipers). Got to work, turned it off, then tried to start it and nothing but clicking 
At the end of the day went out to the Jeep with a buddy prepared to give me a jump and the damn thing started right up with no jump
Had the battery tested today at Sears just to be sure and it checked out just fine...fully charge no problems.
What else could have gone wrong to throw the battery light warning and the power loss? Would the dealer be able to look back and pull any diagnostic codes or are they just going to tell me to bring it in the next time it happens?
BTW - It's the original battery, 32K miles and a few extra accessories running from it (Brake Controller, CB, occasional air compressor and winch)
At the end of the day went out to the Jeep with a buddy prepared to give me a jump and the damn thing started right up with no jump
Had the battery tested today at Sears just to be sure and it checked out just fine...fully charge no problems.
What else could have gone wrong to throw the battery light warning and the power loss? Would the dealer be able to look back and pull any diagnostic codes or are they just going to tell me to bring it in the next time it happens?
BTW - It's the original battery, 32K miles and a few extra accessories running from it (Brake Controller, CB, occasional air compressor and winch)
01-06-2009, 10:30 AM
#13
JK Junkie
Happens to me and Rhonda when doing deep snow, snow gets up onto the sepertine belt and causes the altenator pully to slip. Only proved this by getting a cigerate light plug in battery/alt tester.
01-06-2009, 12:12 PM
#14
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Finally got our first major snow this past week and of course I HAD to go play in it
While navigating some deep snow the battery warning light came on and all my electrics seemed to be loosing power, lights were dimming etc. . Shut it down and restarted and the lihjts were back to full power and no warning light. Went back to playing and everytime I was dragging the frame in deep snow it happened again....... ARGHHHH. Am I alone with this issue?
Packman
While navigating some deep snow the battery warning light came on and all my electrics seemed to be loosing power, lights were dimming etc. . Shut it down and restarted and the lihjts were back to full power and no warning light. Went back to playing and everytime I was dragging the frame in deep snow it happened again....... ARGHHHH. Am I alone with this issue?Packman
the only time my light came on was during a 45 minute hard pull when i was recovering a flipped 08 rubicon in a ravine... very sad..
01-28-2009, 05:05 PM
#15
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Tsb 18-036-06
I had my JK into the dealership today for the battery light. My light use to come on after a near stall.
If I stopped shutdown and restarted the light was gone away. But if I didn’t stop and continued driving with the light on the dash would light up like a Christmas tree and things would start shutting down starting with the radio. So after reading this thread I mentioned TSB 18-036-06 when I dropped it off (service writers hate that, use to be one at a Ford dealer
) After picking it up I inquired what had been done and the work order only said that the power train module had been flashed. It’s too early to say if it fixed my battery light or not but, there is a big improvement in throttle response below 2000 RPM. Tell the truth I don’t really care if the battery light comes on again. The flash is worth getting done if your JK hasn’t hade it done yet and it fits the TSB parameters. 
Hope the fuel mileage improves also as others have posted.
If I stopped shutdown and restarted the light was gone away. But if I didn’t stop and continued driving with the light on the dash would light up like a Christmas tree and things would start shutting down starting with the radio. So after reading this thread I mentioned TSB 18-036-06 when I dropped it off (service writers hate that, use to be one at a Ford dealer) After picking it up I inquired what had been done and the work order only said that the power train module had been flashed. It’s too early to say if it fixed my battery light or not but, there is a big improvement in throttle response below 2000 RPM. Tell the truth I don’t really care if the battery light comes on again. The flash is worth getting done if your JK hasn’t hade it done yet and it fits the TSB parameters. Hope the fuel mileage improves also as others have posted.
Last edited by jklew98; 01-29-2009 at 05:43 AM.
02-03-2010, 11:59 AM
#16
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It happened to me yesterday. On my commute to work the battery light came on and the accessories started to lose power (radio, fog lights, wipers). Got to work, turned it off, then tried to start it and nothing but clicking
At the end of the day went out to the Jeep with a buddy prepared to give me a jump and the damn thing started right up with no jump
Had the battery tested today at Sears just to be sure and it checked out just fine...fully charge no problems.
What else could have gone wrong to throw the battery light warning and the power loss? Would the dealer be able to look back and pull any diagnostic codes or are they just going to tell me to bring it in the next time it happens?
BTW - It's the original battery, 32K miles and a few extra accessories running from it (Brake Controller, CB, occasional air compressor and winch)
At the end of the day went out to the Jeep with a buddy prepared to give me a jump and the damn thing started right up with no jump
Had the battery tested today at Sears just to be sure and it checked out just fine...fully charge no problems.
What else could have gone wrong to throw the battery light warning and the power loss? Would the dealer be able to look back and pull any diagnostic codes or are they just going to tell me to bring it in the next time it happens?
BTW - It's the original battery, 32K miles and a few extra accessories running from it (Brake Controller, CB, occasional air compressor and winch)
I checked the codes and it's throwing the following:
P2503 Charging System Output Low
P2504 Charging System Output High
It goes in the shop tomorrow so we'll see what they find.
02-04-2010, 09:08 AM
#17
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Wow, all these ecu problems? Makes you wonder about then now. Mercedes is coming out with a ecu program that stops your car if your going to hit somthing! Think what happens when that screws up.
12-15-2010, 04:50 AM
#18
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Well it's been over a year since I had this problem and over 6 months since I've replaced my factory battery with a Optima Yellow Top and my battery light is on again.
I checked the codes and it's throwing the following:
P2503 Charging System Output Low
P2504 Charging System Output High
It goes in the shop tomorrow so we'll see what they find.
I checked the codes and it's throwing the following:
P2503 Charging System Output Low
P2504 Charging System Output High
It goes in the shop tomorrow so we'll see what they find.
12-15-2010, 06:13 AM
#19
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12-15-2010, 10:29 AM
#20
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