Communications Network
Pinpoint Test O: The Driver Seat Module (DSM) Does Not Respond To The Scan Tool
Refer to Wiring Diagram Set 14, Module Communications Network for schematic and connector information Electrical Diagrams.
Refer to Wiring Diagram Set 123, Memory Seats for schematic and connector information Electrical Diagrams.
Normal Operation
The Driver Seat Module (DSM) communicates with the scan tool through the Medium Speed Controller Area Network (MS-CAN).
This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- DSM (Driver Seat Module)
PINPOINT TEST O : THE DSM (Driver Seat Module) DOES NOT RESPOND TO THE SCAN TOOL
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
NOTE: Failure to disconnect the battery when instructed results in false resistance readings.
O1 CHECK THE DSM (Driver Seat Module) VOLTAGE SUPPLY CIRCUITS FOR AN OPEN
- Ignition OFF.
- Disconnect: DSM (Driver Seat Module) C3299A.
- Disconnect: DSM (Driver Seat Module) C3299B.
- Measure the voltage between the DSM (Driver Seat Module) C3299A-1, circuit SBB23 (WH/RD), harness side and ground.
- Measure the voltage between the DSM (Driver Seat Module) C3299B-1, circuit SBP07 (WH/RD), harness side and ground.
Are the voltages greater than 10 volts?
Yes
GO to O2.
No
VERIFY the Battery Junction Box (BJB) fuse 23 (30A) and the Body Control Module (BCM) fuse 7 (7.5) is OK. If OK, REPAIR the circuit in question. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short Electrical Diagrams. CLEAR the DTCs. REPEAT the network test with the scan tool.
O2 CHECK THE DSM (Driver Seat Module) GROUND CIRCUIT FOR AN OPEN
- Disconnect: Negative Battery Cable.
- Measure the resistance between the DSM (Driver Seat Module) C3299A-2, circuit GD145 (BK/BU), harness side and ground.
- Measure the resistance between the DSM (Driver Seat Module) C3299B-24, circuit GD133 (BK), harness side and ground.
Are the resistances less than 5 ohms?
Yes
GO to O3.
No
REPAIR the circuit in question. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the network test with the scan tool.
O3 CHECK THE MS-CAN (Medium Speed Controller Area Network) CIRCUITS BETWEEN THE DSM (Driver Seat Module) AND THE DLC (Data Link Connector) FOR AN OPEN
- Disconnect: DSM (Driver Seat Module) C3299D.
- Measure the resistance between the DSM (Driver Seat Module) C3299D-10, circuit VDB06 (GY/OG), harness side and the DLC (Data Link Connector) C251-3, circuit VDB06 (GY/OG), harness side.
- Measure the resistance between the DSM (Driver Seat Module) C3299D-9, circuit VDB07 (VT/OG), harness side and the DLC (Data Link Connector) C251-11, circuit VDB07 (VT/OG), harness side.
Are the resistances less than 5 ohms?
Yes
CONNECT the negative battery cable. GO to O4.
No
REPAIR the circuit in question. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the network test with the scan tool.
O4 CHECK FOR CORRECT DSM (Driver Seat Module) OPERATION
- Disconnect all the DSM (Driver Seat Module) connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the DSM (Driver Seat Module) connectors and make sure they are seated correctly.
- Operate the system and verify the concern is still present.
Is the concern still present?
Yes
INSTALL a new DSM (Driver Seat Module). REPEAT the network test with the scan tool.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the network test with the scan tool.