锟斤拷 If the test lamp illuminates, test the control circuits listed below for a short to voltage:
* Driver seat cushion and back element terminal 14 X1
* Driver seat cushion element terminal 11 X1
* Driver seat back element terminal 1 X1
5. Verify that a test lamp does not illuminate between the supply voltage circuit terminal 6 X1 and ground.
锟斤拷 If the test lamp illuminates, test the control circuits listed below for a short to voltage:
* Passenger seat cushion and back element terminal 6 X1
* Passenger seat cushion element terminal 14 X4
* Passenger seat back element terminal 4 X1
6. If all circuits test normal, replace the MSM.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Driver or Passenger Seat Back Cushion Heater Replacement (Escalade with HP2) ()Driver or Passenger Seat Back Cushion Heater
Replacement (Tahoe with HP2) ()Driver or Passenger Seat Back Cushion Heater Replacement (without HP2) ()
* Driver or Passenger Seat Cushion Heater Replacement (without HP2) ()Driver or Passenger Seat Cushion Heater Replacement (with HP2)
()
* Control Module References (See: Testing and Inspection/Programming and Relearning) for the MSM replacement, setup, and programming
Dealer Installed
DTC B2508 or B2509 (Dealer Installed)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC B2508 01
- Seat Heater Relay Circuit Short to Battery
DTC B2508 02
- Seat Heater Relay Circuit Short to Ground
Diagnostic Fault Information
