Pinpoint Test P : The DSM (Driver Front Seat Module) Does Not Respond To The Diagnostic Scan Tool

WARNING: This page is about a different car, the 2020 Ford Mustang. However, it is still accessible from the selected car via links, so may be relevant.

Refer to Module Communications Network for schematic and connector information. Refer to Climate Controlled Seats for schematic and connector information.
Normal Operation and Fault Conditions

The DSM communicates on the MS-CAN.

Possible Sources
- Fuse
- Wiring, terminals and connector
- DSM
Visual Inspection and Pre-checks
- Verify BJB fuse 12 (30A) is OK.

P1 CHECK THE DSM (DRIVER FRONT SEAT MODULE) VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

Ignition OFF.

Disconnect: DSM C341B.

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C341B-10	Courtesy of FORD MOTOR COMPANY	Ground

Is the voltage greater than 11 volts?

Yes

GO to P2

No	VERIFY BJB fuse 12 (30A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the Introduction to identify the possible causes of the circuit short.

P2 CHECK THE DSM (DRIVER FRONT SEAT MODULE) GROUND CIRCUITS FOR AN OPEN

Ignition OFF.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C341C-7	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance less than 3 ohms?

Yes

GO to P3

No	REPAIR the circuit in question.

P3 CHECK THE MS-CAN (MEDIUM SPEED-CONTROLLER AREA NETWORK) CIRCUITS BETWEEN THE DSM (DRIVER FRONT SEAT MODULE) AND THE GWM (GATEWAY MODULE A) FOR AN OPEN

Disconnect DSM C341A.

Disconnect GWM C2431.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C341D-2	Courtesy of FORD MOTOR COMPANY	C2431-23
C341D-3	Courtesy of FORD MOTOR COMPANY	C2431-22

Are the resistances less than 3 ohms?

Yes

GO to P4

No	REPAIR the circuit in question.

P4 CHECK FOR CORRECT DSM (DRIVER FRONT SEAT MODULE) OPERATION

Ignition OFF.

Disconnect and inspect all the DSM connectors.

Repair:
- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary

Reconnect the DSM connectors. Make sure they seat and latch correctly.

Operate the system and determine if the concern is still present.

Is the concern still present?

Yes

CHECK OASIS for any applicable service articles: TSB, General Service Bulletin (GSB), SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new DSM. REFER to: Driver Front Seat Module (DSM) .

No	The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.