Diesel Data: Automotive Repair

Totally Integrated Power Module (TIPM)






U0022-CAN B BUS (+) CIRCUIT LOW

For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:
Continuously.

- Set Condition:
The Totally Integrated Power Module (TIPM) detects the (D55) CAN B Bus (+) circuit is shorted to ground.





Diagnostic Test

1. TEST FOR INTERMITTENT CONDITION

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

1. Turn the ignition on.
2. With the scan tool, record and erase TIPM DTCs.
3. Cycle the ignition from on to off three times.
4. Turn the ignition on.
5. With the scan tool, read active TIPM DTCs.

Does the scan tool display this DTC as active?

Yes
- Go To 2

No
- Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.

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




1. Turn the ignition off.
2. Disconnect the TIPM C5 harness connector.
3. Measure the resistance between ground and the (D55) CAN B Bus (+) circuit.

Is resistance below 1000.0 Ohms?

Yes
- Go To 3

No
- Inspect the wiring and connectors for damage or shorted circuits. If OK, replace the Totally Integrated Power Module.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

3. CHECK THE (D55) CAN B BUS (+) CIRCUIT FOR A SHORT TO GROUND




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

NOTE: This is to determine if the circuit is shorted to ground internally within a module or if the circuit is shorted 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
- Repair the short to ground in the (D55) CAN B Bus (+) circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No
- Replace the module that when disconnected eliminated the short to ground.
- Perform the BODY VERIFICATION TEST. Body Verification Test.