Heated Seats
U0019-CAN B BUS - HSMU0019 - Can B Bus - HSM:
WHEN MONITORED
Continuously
SET MONITORED
Whenever the Can B Bus (+) or 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
- (D54) CAN B Bus (-) circuit open
- (D55) CAN B Bus (+) circuit open
- Heated seat 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 U0019 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 the symptom list for problems related to Communication in the ELECTRICAL - ELECTRONIC CONTROL MODULES - ELECTRICAL DIAGNOSES section.
NO: Go to 3
3. CAN B BUS (+) CIRCUIT OPEN
Turn the ignition off.
Disconnect the Heated Seat Module 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 Heated Seat Module connector.
Q: Is the resistance below 2.0 ohms?
YES: Go To 4
NO: Repair the Can B Bus (+) circuit for an open. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
4. CAN B BUS (-) CIRCUIT OPEN
Measure the resistance of the (D54) Can B Bus (-) circuit between the Front Control Module C1 connector and the Heated Seat Module connector.
Q: Is the resistance below 2.0 ohms?
YES: Replace the Heated Seat 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