M/T - ZF GS6-37 SMG Engine Stall on Deceleration/MIL ON
SI B 23 03 04Manual Transmission
July 2004
Technical Service
SUBJECT
E46 M54: SMG Transmission Relay Failure
MODEL
E46 with ZF GS6-37 SMG up to 07/04 production
SITUATION
A customer may complain about following conditions:
^ Engine stalls intermittently during deceleration.
^ EML and Check Engine Light may be illuminated briefly while the SMG transmission may switch from cruise control or automatic mode into the manual/sequential mode.
^ At the same time, the Sport mode maybe deactivated.
CAUSE
Defective SMG relay is causing the DME to reset due to excessive voltage drop.
CORRECTIONS
On a customer complaint basis, retrofit improved SMG relay and adaptor harness (PN 12 63 7 545 666).
PROCEDURE
1. Disconnect battery.
2. Remove E-box cover.
3. Disconnect all connectors at SMG and DME control modules.
4. Remove SMG relay (# 2 - salmon colored).
5. Lift the relay carrier out of the centering pins (# 1) and rotate it so that the SMG relay socket becomes accessible.
6. Remove the SMG relay socket.
7. Cut four wires at the SMG relay socket close to the connectors.
8. Strip the insulation to the length of 4 mm.
9. Using a crimping tool (PN 81 24 9 408 449 from the Electrical Kit III), crimp new terminals (found in the retrofit kit) with the following contact assignment:
0.5 mm 2 - brown and brown/black (# 1 - small pin)
4.0 mm 2 - red and red/yellow (# 2 - larger pin).
10. Insert the wires with female contacts into the new connector (# 1).
11. The wire sequence is as follows:
Pin # 1 - Brown/black
Pin # 2 - Brown
Pin # 3 - Red/yellow
Pin # 4 - Red.
12. From the bottom insert the new relay and relay socket (# 1) into the relay carrier.
13. Secure the adapter harness (# 3) with connector (# 2) to the existing harness with an electrical tie.
14. Reinstall the relay carrier making sure that centering pins (# 1) are snapped into position.
15. Reconnect all connectors; reinstall E-box cover.
16. Reconnect battery.
17. Perform "SMG teaching procedure" using DIS/GT1 (found in Service Function/Drive path).
PARTS INFORMATION
WARRANTY INFORMATION
Covered under the terms of the BMW New Vehicle Limited Warranty.