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Discussion Starter #1
I got into my '07 this morning and it was 38 degrees. I decided to turn the heated seats on. When I press the switch for both the driver and passenger side nothing happens. The lights don't come on and neither warm up. Power seats still work and all the other switches on that row work. Seems to be a fuse? Can anyone tell me what fuse it would be? Thanks guys.


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Discussion Starter #3
Yeah I checked wkjeeps with no luck. I also googled for a while and found nothing. I REALLY don't want to bring it to the dealership.


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"guy with the crazy Jeep"
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Looks like a lot to look at. More then likely a dealer issue.

I found a lot of information in the service manual, but here is one page out of it.
 

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It is probably the fuse. I'm not sure which one, but it is the box under the hood.

Just pull them out and see what/if any are blown.
 

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"guy with the crazy Jeep"
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OPERATION
The heated seat system operates on battery current received through a fuse in the Integrated Power Module (IPM). The heated seat module (HSM) is fed by a B+ circuit and continues to receive power regardless of ignition key position. The HSM monitors the ignition status message on the Controller Area Network (CAN) data bus. If the ignition state is ON/RUN then the HSM will power the heating elements. The heated seat system will turn Off automatically whenever the ignition switch is turned to any position except ON/RUN.

When either of the heated seat switches are depressed a resistance signal is sent to the Cab Compartment Node (CCN) or instrument cluster. The CCN then sends a message via the CAN data bus to the heated seat module, signaling the module to energize the heating element for the selected seat. Amber Light Emitting Diodes (LEDS) in the top portion of each switch indicate the level of heat in use: Two LEDs are illuminated for high, one for low, and none for off. Pressing the switch once will select high-level heating. Pressing the switch a second time will select low-level heating. Pressing the switch a third time will shut the heating elements off.

The heated seat module energizes an integral solid-state relay, which supplies battery current to the heating elements. When high-temperature heating is selected, the heaters provide a boosted heat level during the first four minutes of operation after heating is activated. The heat output then drops to the normal high-temperature level. If high-level heating is selected, the control system will automatically switch to the low level after two hours of continuous operation. At that time, the number of illuminated LEDs changes from two to one, indicating the change. Operation on the low setting also turns off automatically after two hours.

The module will automatically turn off the heating elements if it detects an OPEN or LOW short in the heating element circuit.
 

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"guy with the crazy Jeep"
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One more thing... Check the battery.

HEATED SEAT SYSTEM
In order to obtain conclusive testing, the heated seat system and the Controller Area Network (CAN) data bus circuit must be checked. Any diagnosis of the heated seat system should begin with, the use of a scan tool and the appropriate diagnostic service information.

Refer to the appropriate wiring information for complete circuit schematic or connector pin-out information.

NOTE: Vehicles equipped with the heated seat option utilize a low voltage cut-off feature. This feature turns off power to the heated seat system anytime vehicle voltage is below 11.7V or above 15.5V. Be certain to check the vehicle electrical system for proper voltage anytime the power seat system appears inoperative.

Before any testing of the heated seat system is attempted, the battery should be fully-charged.
 

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I had this problem a month ago, I have a 2008 but give this a try. Here is the text from the TSB from WK jeeps.

NOTE: This bulletin applies to vehicles built before July 20, 2007 (MDH 0720XX)
equipped with sales code JPM only (only front heated seats).
SYMPTOM/CONDITION:
The front heated seat will be inoperative. The front HSM did not learn the proper vehicle
configuration causing this condition. Disconnecting and reconnecting the front HSM will
allow the front HSM to be configured correctly with the vehicle line information
DIAGNOSIS:
If the vehicle operator experiences the condition, perform the Repair Procedure.
REPAIR PROCEDURE:
1. Remove ignition key from ignition switch.
2. Disconnect and reconnect the heated seat module connector. The module can be
accessed from under the front right seat with the seat in the full back position.
3. Start vehicle. Activate the front heated seats. If front heated seats LED comes on for
two seconds and go off then further diagnosis is required.
 

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Discussion Starter #9
Thanks guys. I will try that stuff tomorrow. I might need a new battery, it's probably the original one.


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Discussion Starter #10
Just wanted to give an update in case anyone else runs into this problem. I disconnected the negative side of the battery for a couple minutes. Then i reconnected it and now my heated seats work. Thanks for all the help.
 
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