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U0021

U0021-CAN B BUS (+) CIRCUIT OPEN


U0021-CAN B BUS (+) Circuit Open:




WHEN MONITORED
Continuously

SET CONDITION
The Memory Seat Module detects the (D55) CAN B Bus (+) circuit is open.

POSSIBLE CAUSES
- (D55) CAN B BUS (+) circuit open
- Memory seat module

DIAGNOSTIC TEST

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

Q: 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.

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




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

Q: 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 - VER 1. Power Seat System Verification Test
NO: Repair the (D55) CAN B Bus (+) circuit for an open. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test