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U1000

U1000-CAN B BUS (+) CIRCUIT- DDM - PDM


U1000-CAN B BUS (+) Circuit - DDM - PDM:





WHEN MONITORED
With the ignition in the run position.

SET CONDITION
If the Driver/Passenger Door Module senses that the (D55) Can B Bus (+) circuit is either open, or shorted to voltage, or shorted to ground.

POSSIBLE CAUSES
- FOR THE DRIVER MEMORY MIRROR SYSTEM:
- Active CAN B BUS DTCs in front control module (FCM)
- (D55) CAN B BUS (+) circuit open to driver door module
- Driver door module

- FOR THE PASSENGER MEMORY MIRROR SYSTEM:
- Active CAN B BUS DTCs in front control module (FCM)
- (D55) CAN B BUS (+) circuit open to passenger door module
- Passenger door module

NOTE: Since this DTC can set in the Driver Door Module (DDM) and in the Passenger Door Module (PDM) this procedure addresses both systems circuits and components. Select only that which applies to the system you are diagnosing.

DIAGNOSTIC TEST

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

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.
Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

2. CHECK FOR ACTIVE CAN B BUS RELATED DTCS IN THE FRONT CONTROL MODULE (FCM)
With the scan tool, read Front Control Module (FCM) DTCs

Q; Does the scan tool display any active CAN B BUS related DTCs?

YES: Diagnose and repair the DTC(s).
NO: Go To 3

3. CHECK THE (D55) CAN B BUS (+) CIRCUIT FOR AN OPEN BETWEEN THE FRONT CONTROL MODULE & THE DRIVER / PASSENGER DOOR MODULE




For the Driver Memory Mirror System, proceed as follows:
- Turn the ignition off.
- Disconnect the Driver Door Module C2 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 Driver Door Module C2 connector.

For the Passenger Memory Mirror System, proceed as follows:
- Turn the ignition off.
- Disconnect the Passenger Door Module C2 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 Passenger Door Module C2 connector.

Q: Is the resistance below 2.0 ohms?

Yes, Driver Mirror
Replace the Driver Door Module.
Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

Yes, Passenger Mirror
Replace the Passenger Door Module.
Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

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