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Test U

PINPOINT TEST U: NO COMMUNICATION WITH THE FRONT ELECTRONIC MODULE (FEM)


Test U1:






Test U1-U2:






Normal Operation
The FEM controls RH exterior mirrors, power adjustable pedals, both interior and exterior lighting active anti-theft functions and the brake shift interlock. Power is supplied through the central junction box (CJB) fuse 20 (10A) and fuse 30 (5A) on Circuits 29-DK20 (OG/GN), 29-DK21 (OG/WH) and grounded through circuit 31-DK20 (BK/RD), 31-DK20A (BK/RD), 31-DK20B (BK/RD), 31-DK20C (BK/RD) and 31-DK20D (BK/RD).

Possible Causes
- CJB fuse 20 (10A)
- CJB fuse 30 (5A)
- circuit 29-DK20 (OG/GN) open or shorted to ground
- circuit 29S-DK22 (OG/WH) open or shorted to ground
- circuit 31-DK20 (BK/RD) open
- circuit 31-DK20A (BK/RD) open
- circuit 31-DK20B (BK/RD) open
- circuit 31-DK20C (BK/RD) open
- circuit 31-DK20D (BK/RD) open
- FEM