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Lost Communication With Powertrain Control Module






U0100 - Lost Communication with Powertrain Control Module

For a complete wiring diagram, refer to.

When Monitored: The ignition ON and battery voltage between 10 and 16 volts. Ignition-off draw fuse installed. Totally integrated power module configured correctly.

Set Condition: Bus messages not received from the PCM for approximately 2 to 5 seconds.






Test Step 1 - Verify the Diagnostic Trouble Code DTC is Active

Ensure the IOD fuse is installed and battery voltage is between 10 and 16 volts before proceeding.

With the scan tool, read active DTCs.

Is this DTC active?

Yes

Go to Test Step 2.

No

Perform the Stored Lost Communication procedure. Refer to => Non-DTC Based Diagnostics.

Test Step 2 - Test for Any of the Following Active DTCs

With the scan tool, read all Active DTCs from all modules.

Test for TIPM configuration, CAN C hardware electrical, VIN Missing/Mismatch, battery or ignition related DTCs.

Does the scan tool display any active DTCs to the conditions listed?

Yes

Perform the appropriate diagnostic procedure.

No

Go to Test Step 3.

Test Step 3 - Verify the PCM is Active on the Bus

Turn the ignition ON.

With the scan tool, select network diagnostics.

Verify the PCM is active on the bus.

Is the PCM active on the bus?

Yes

Go to Test Step 4.

No

Perform the No Response diagnostic procedure. Refer to => Non-DTC Based Diagnostics.

Test Step 4 - Test for Additional Communication Related DTCs

With the scan tool, select network diagnostics.

Is there more than one module with Active DTCs logged against the PCM?

Yes

Replace and configure the PCM.

Perform the appropriate Verification Test.

No

Go to Test Step 5.

Test Step 5 - Clear DTC in Module Setting Fault

With the scan tool, select the module setting the DTC against the PCM.

Clear Active DTCs.

Is this DTC still active?

Yes

Replace/update the module that set this DTC.

Perform the appropriate Verification Test.

No

Go to Test Step 6.

Test Step 6 - Cycle Ignition

Cycle the ignition from RUN to OFF three times ending with the key in the RUN position.

Does this DTC become active?

Yes

Go to Test Step 7.

No

The condition is not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring for chafed, pierced, pinched, and partially broken wires and the wiring harness connectors for broken, bent, pushed out, and corroded terminals.

Perform the appropriate Verification Test.

Test Step 7 - Test for Additional Lost Communication Faults

With the scan tool, select network diagnostics.

Do the TIPM and other CAN C bus modules show lost communication with the remaining CAN C bus modules?

Yes

Go to Test Step 8.

No

Replace/update the module that set this DTC.

Perform the appropriate Verification Test.

Test Step 8 - CAN C Bus (+) Circuit Short to Voltage

Measure the voltage between the CAN C bus (+) circuit and ground.

Is the voltage more than 5 volts?

Yes

Repair the circuit for a short to voltage.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

No

Go to Test Step 9.

Test Step 9 - CAN C Bus (-) Circuit Short to Ground

Turn the ignition OFF.

Measure the resistance between ground and the CAN C bus (-) circuit.

Is the resistance less than 10K Ohms?

Yes

Repair the circuit for a short to ground.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

No

Replace/update the module that set this DTC.

Perform the appropriate Verification Test.