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U1000

U1000 - CAN B BUS (+) CIRCUIT- MEMORY MIRROR MODULE

U1000 - CAN B BUS (+) Circuit - Memory Mirror Module:






WHEN MONITORED
Continuously.

SET CONDITION
Whenever the Can B Bus (+) circuit is open, shorted to voltage or shorted to ground, this code will set.

POSSIBLE CAUSES
- CAN B BUS (+) DTC's in front control module
- (D55) CAN B BUS (+) circuit open
- Memory mirror module

Diagnostic Test

1. TEST FOR INTERMITTENT CONDITION

Turn the ignition on.
With the scan tool, record and erase DTC's
Cycle the ignition from on to off 3 times.
Turn the ignition on.
With the scan tool, read DTC's.

Q: Does the scan tool display U1000 CAN B BUS (+) CIRCUIT?

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. CHECK FRONT CONTROL MODULE DTC's

With the scan tool, read Front Control Module DTC's

Q: Does the scan tool display any CAN B BUS DTC's - ACTIVE?

YES: Refer to Manufacturer Code Charts for problems related to Communication.
NO: Go to 3

3. CAN B BUS (+) CIRCUIT OPEN




Turn the ignition off.
Disconnect the appropriate Memory Mirror Module C1 connector.
Disconnect the Front Control Module C1 connector.
Measure the resistance of the (D55) Can B Bus (+) circuit between the Front Control Module C1 connector and the Memory Mirror Module connector.

Q: Is the resistance below 2.0 ohms?

YES: Replace the Memory Mirror Module. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Repair the Can B Bus (+) circuit for an open. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test