Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Test I: The Driver Seat Module (DSM) Does Not Respond To The Diagnostic Tool

PINPOINT TEST I: THE DRIVER SEAT MODULE (DSM) DOES NOT RESPOND TO THE DIAGNOSTIC TOOL


I1-I2:






I2-I3:






I4-I5:






I5-I6:






I7:






Normal Operation
The DSM communicates with the diagnostic tool through the standard corporate protocol (SCP) communications network circuits 4-AH80 (GY/WH) and 5-AH80 (BU/OG). If circuit 4-AH80 (GY/WH) or 5-AH80 (BU/OG) becomes open or shorted to ground, communications to that module are not possible. Check circuits 4-AH80 (GY/WH) and 5-AH80 (BU/OG) between the DSM C341c and the data link connector (DLC) C251. The total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms, there is either an open in circuit 4-AH80 (GY/WH) or 5-AH80 (BU/OG), damage to the DLC C251, damage to the DSM C341c, or a problem with the interior auxiliary junction box (AJB) C283c, interior AJB C283d or joint connector No. 4 C223.

Possible Causes
- SCP data plus circuit 4-AH80 (GY/WH) open
- SCP data minus circuit 5-AH80 (BU/OG) open
- joint connector No. 4 C223
- interior AJB C283c
- interior AJB C283d
- DSM C341c
- DSM