Affected Component: SEATS

Date Published
NOV 18, 2016
NHTSA TSB #
10114840
TSB Document
Summary
This Preliminary Information communication provides information to the technician only to provide additional tips when diagnosing a front heated seat concern and is not meant to be a diagnostic flow chart or replace Service Information. Always, perform and refer to Service Information for the latest diagnostic information and procedures. Trucks equipped with heated and cooled seats Regular Production Option Code (KB6), may comment on any of the following front heated seat concerns. Condition 1, a front heated seat (back and/or cushion) is inoperative. Technician should diagnosis each affected seat heater individually. Technician should test all four circuits Power, Ground, Control (from Body Control Module) and Heating Element Supply Power. The Power, Ground, Control (from Body Control Module) can easily be checked by starting the engine and turn on the cooled seat. When the cooled seats are turned on the blower in each seat back and cushion will turn on at that point technician will be able to hear the blower moving. The heating element supply power circuit can be test by disconnecting the affected heating element and connect a voltmeter across the heating element supply power and ground circuit. Then start the engine and turn on the heated seat, the blower will supply system voltage on the element supply power circuit for 1 to 2 seconds. With the heated seat element disconnected, use an ohmmeter to measure the resistance of the heating element. If all of the above steps check ok or the heating element resistance is close to the approximate spec, reconnect all disconnected connectors. Connect a voltmeter across the affected heated seat element connectors supply power and ground circuits back probing the connector. Then check the resistance of the heating element. The resistance should be close to the same resistance as when testing with the connector unplugged. Now check the voltage with the engine running and the heated sets on high. Condition 2, the front heate