Interior - Front Seat Heater Activates On It's Own

2010 BMW 335Cic Convertible (E93) L6-3.0L Turbo (N54) Technical Service Bulletin # 521210 Date: 101201

Interior - Front Seat Heater Activates On It's Own

2010 BMW 335Cic Convertible (E93) L6-3.0L Turbo (N54) 245

SI B52 12 10

Seats

December 2010

Technical Service

SUBJECT

Seat Heating Activates On Its Own

MODEL

E82, E88 (1 Series)

E90, E91, E92, E93 (3 Series)

Only vehicles equipped with SA 494 (Front Seat Heating) and SA 534 (Integrated Automatic Air Conditioning)

Only vehicles produced from 8/31/2009 to 2/25/2010

SITUATION

The front seat heating sporadically activates on its own.

CAUSE

Defective plug-in contacts in the wiring between the SZM (Center Console Switch Cluster) and the IHKA (Integrated Automatic Air Conditioning)

control panel

PROCEDURE

Perform diagnostics using ISTA (Integrated Service Technical Application) for any fault codes that may pertain to the seat heating function. Follow

the procedure as outlined below if standard diagnosis does not identify the problem.

1. Remove the IHKA control panel as per ISTA Repair Manual "REP 61 11 377" (without CIC Car Information Computer) or "REP 64 11 378"

(with CIC).

2. Remove the SZM as per ISTA Repair Manual "REP 61 31 052" (without CIC) or "REP 61 31 054" (with CIC).

3. Check the ribbon cable harness that comes from the SZM and plugs into the IHKA control panel for loose or damaged contacts.

4. If the cable harness is damaged, replace the SZM using the repair kit P/N 61 31 9 120 026

5. If the cable harness is not damaged, the repair outlined in this service information bulletin does not apply. Continue troubleshooting.

PARTS INFORMATION

WARRANTY INFORMATION

Covered under the terms of the BMW New Vehicle/SAV Limited Warranty as applicable, or the Certified Pre-owned Program.