Seat Temperature Control Module: Testing and Inspection

Checking Seat Heating Module (SHM)

Fault-tracing information





This troubleshooting only applies to vehicles that have problems with the climate units and seat heating.
Example of symptoms is uneven temperature of air supply for left and right sides of the passenger compartment as well as lost function for seat heating.

NOTE: Before starting this symptom troubleshooting, check that no relevant diagnostic trouble codes are stored for the vehicle's climate unit.

Climate control module (CCM) and seat heating module communicates via standardized serial communication - LIN (Local Interconnect Network). If Seat Heating Module (SHM) is damaged, this may cause problems with both climate unit and seat heating. Then it is not possible to perform calibration of Climate control module (CCM).

To check if Seat Heating Module (SHM) driver side is damaged, do the following:

1. Disconnect Seat Heating Module (SHM), driver's side.
2. Check if the climate unit works correctly.

If the climate unit works correctly without Seat Heating Module (SHM) driver's side connected, then Seat Heating Module (SHM) driver's side shall be replaced.

3. Do the same check on Seat heating module (SHM), passenger side.

Remedy as necessary.