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Memory Seat Module (MSMD)






U0020-CAN B BUS OFF PERFORMANCE





For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:
Continuously.

- Set Condition:
The Memory Seat Module detects the (D55) CAN B Bus (+) circuit or (D54) CAN B Bus (-) circuit open.





1. TEST FOR INTERMITTENT CONDITION
1. Turn the ignition on.
2. With the scan tool, record and erase MSM DTC's
3. Cycle the ignition from on to off 3 times.
4. Turn the ignition on.
5. With the scan tool, read active MSM DTC's.

Does the scan tool display this DTC as active?

Yes

- Go To 2

No

- The conditions that caused this code to set are not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
- Perform BODY VERIFICATION TEST. Body Verification Test.

2. (D55) CAN B BUS (+) CIRCUIT OPEN




1. Turn the ignition off.
2. Disconnect the Memory Seat Module C1 harness connector.
3. Measure the voltage between the (D55) CAN B Bus (+) circuit and ground.

Is there any voltage present?

Yes

- Go To 3

No

- Repair the (D55) CAN B Bus (+) circuit for an open.
- Perform BODY VERIFICATION TEST. Body Verification Test.

3. (D54) CAN B BUS (-) CIRCUIT OPEN




1. Turn the ignition off.
2. Disconnect the Memory Seat Module C1 harness connector.
3. Measure the voltage between the (D54) CAN B Bus (-) circuit and ground.

Is there any voltage present?

Yes

- Inspect the wiring and connectors for damage or shorted circuits. If ok, replace the Memory Seat Module.
- Perform POWER SEAT SYSTEM VERIFICATION TEST. Power Seat System Verification Test.

No

- Repair the (D54) CAN B Bus (-) circuit for an open.
- Perform BODY VERIFICATION TEST. Body Verification Test.