2007 Compass Patriot MK Factory Service Manual 8 - ELECTRICAL

U0027-CAN B BUS (-) SHORTED TO BUS (+)





For a complete wiring diagram Refer to Section 8W.



Possible Causes
 
(D55) CAN B BUS (+) CIRCUIT SHORTED TO THE (D54) CAN B BUS (-) CIRCUIT
 
ANY CAN B BUS MODULE
 
TOTALLY INTEGRATED POWER MODULE
 




Diagnostic Test

1. TEST FOR INTERMITTENT CONDITION

NOTE: Check for any TSB(s) related to the condition. If a TSB applies, perform the procedure outlined in the TSB before continuing.


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

Does the scan tool display this DTC as active?

Yes


No

2. CHECK THE (D55) CAN B BUS (+) CIRCUIT FOR A SHORT TO THE (D54) CAN B BUS (-) CIRCUIT



Turn the ignition off.
Disconnect the Totally Integrated Power Module C3 harness connector.
Measure the resistance between the (D55) CAN B Bus (+) circuit and (D54) CAN B Bus (-) circuit.

Is resistance below 1000.0 ohms?

Yes


No

3. (D55) CAN B BUS (+) CIRCUIT SHORTED TO THE (D54) CAN B BUS (-) CIRCUIT



Measure the resistance between the (D55) CAN B Bus (+) circuit and (D54) CAN B Bus (-) circuit.
While monitoring the ohmmeter, disconnect each CAN B Bus module one at a time.

NOTE: This is to determine if the circuits are shorted together internally within a module or if the circuits are shorted together in the harness.


NOTE: Disconnecting an in-line connector can eliminate a module or group of modules from the list of possible causes for this fault. Refer to the wring diagrams to assist in diagnosis.



Is resistance below 1000.0 ohms with all the CAN B Bus modules disconnected?

Yes


No