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HOMESERVICE MANUALSCHRYSLER1999LHSREPAIR AND DIAGNOSIS (SINGLE PAGE)QUICK LOOKUPSTECHNICAL BULLETINSTECHNICAL SERVICE BULLETINSSEATSERRONEOUS "HEATED SEAT SWITCH MISSING/SHORTED" DTC (08-26-99)
1999 Chrysler LHS

Erroneous "Heated Seat Switch Missing/Shorted" DTC (08-26-99)

1999 Chrysler LHSSECTION Erroneous "Heated Seat Switch Missing/Shorted" DTC (08-26-99)
Publication date: 1999-08-06
Reference number: 08-26-99

ERRONEOUS "HEATED SEAT SWITCH MISSING/SHORTED" DTC

ERRONEOUS "HEATED SEAT SWITCH MISSING/SHORTED" DTC

TECHNICAL SERVICE BULLETIN

Reference Number(s): 08-26-99, Date of Issue:  August 6, 1999

ERRONEOUS "HEATED SEAT SWITCH MISSING/SHORTED TO GROUND" DTC

Model(s): 1999-2000 Chrysler (LH) LHS, 300M

Group: Electrical

Bulletin No.: 08-26-99

Date: August 6, 1999

NOTE: This bulletin applies to vehicles built after May 10, 1999 (MDH 0510XX).

SYMPTOM/CONDITION

Diagnostic Trouble Codes (DTC's) "Driver and Passenger Heated Seat Switch Missing/Shorted to Ground" may be set when ignition is cycled from ON to OFF. The heated seat switch will lose power prior to the Memory Heated Seat/Mirror Module (MHSMM) receiving an ignition OFF message from the Body Control Module (BCM). It will appear as if the switch is not connected to the MHSMM, setting the faults. This will not occur on every ignition ON to OFF transition.

DIAGNOSIS

The following procedure will assure that if the DTC's are present, they were set due to the above condition, and a true fault condition does not exist:

  1. Clear all MHSMM faults.
  2. Turn vehicle ignition ON. Using a DRB III verify that the heated seat switch voltage is approximately 1 V when the switch is in the "off" position.
  3. If the voltage reading is 0 V, verify that the switch connector is plugged in properly. If so, follow repair procedures outlined in 1998 Chrysler Concorde/Dodge Intrepid / 1999 300M/LHS Body Diagnostic Procedure Manual (Publication No. 81-270-97229) Memory System Tests 25A and 32A.
NOTE: MHSMM fault counters will be reset after 20 ignition cycles.

WARRANTY INFORMATION

POLICY: Information Only.

RENDER: 1.0x

NO RELATED

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