U0019–CAN B BUS (ATC)





For a complete wiring diagram Refer to Section 8W.


  • When Monitored:

    Continuously

  • Set Condition:

    If the CAN B Bus (+) or CAN B Bus (-) circuit is open, shorted to voltage, or shorted to ground.


Possible Causes
  
ACTIVE U0019 CAN B BUS DTC IN FRONT CONTROL MODULE
  
(D55) CAN B BUS (+) CIRCUIT OPEN
  
(D54) CAN B BUS (-) CIRCUIT OPEN
  
A/C HEATER CONTROL
  



Diagnostic Test

1.VERIFY DTC U0019–CAN B BUS IS ACTIVE




Does the scan tool display active: U0019–CAN B BUS?

Yes
  • Go To 2


No
  • If the DTC is stored, check for an intermittent condition by inspecting the related wiring harness for chafed, pierced, pinched, and partially broken wires. Also, inspect the related connectors for broken, bent, pushed out, spread, corroded, or contaminated terminals.
  • Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).

2.CHECK FOR ACTIVE CAN B BUS RELATED DTCS IN THE FRONT CONTROL MODULE (FCM)



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

Yes


No
  • Go To 3

3.CHECK (D55) CAN B BUS (+) CIRCUIT FOR AN OPEN









Is the resistance below 2.0 ohms?

Yes
  • Go To 4


No

4.CHECK (D54) CAN B BUS (–) CIRCUIT FOR AN OPEN





Is the resistance below 2.0 ohms?

Yes


No