Operation CHARM: Car repair manuals for everyone.

Through Model Year 2011






Stored Lost Communication DTCs






For a complete wiring diagram, refer to.

When Monitored: With the ignition on. Battery voltage between 10 and 16 volts. Ignition Off Draw (IOD) fuse installed. Totally Integrated Power Module (TIPM) is configured correctly.

Set Condition: Bus messages not received for approximately two to five seconds.






Test Step 1 - VERIFY THE DIAGNOSTIC TROUBLE CODE (DTC) IS STORED

Stored faults may indicate a customer perceived intermittent condition.

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

With the scan tool, read stored DTCs.

Is this DTC stored?

Yes

Go to Test Step 2

No

Diagnose the active DTC. Select and perform the appropriate diagnostic procedure.

Test Step 2 - CHECK THE ENVIRONMENTAL DATA

With the scan tool, read the loss of communication environmental data.

Does the loss of communication environmental odometer data match up to any of the previous service procedures listed in the possible causes or are their any stored CAN hardware electrical, battery, ignition voltage, VIN missing/mismatch, TIPM configuration DTCs present with matching environmental data?

Yes

These DTCs may have been the result of other service procedures performed. Clear DTCs.

No

Go to Test Step 3

Test Step 3 - VERIFY INTERMITTENT LOST COMMUNICATION DTC OR WIRING CONCERNS

Turn the ignition on.

With the scan tool, select Network View and select Advanced.

Is there more than one ECU with stored DTCs "Logged Against" the module and one or more lost communication DTCs stored in the offending module?

Yes

Verify if the vehicle was recently in for this type of service. Otherwise, visually inspect the related wiring harness for chafed, pierced, pinched, and partially broken wires and the wiring harness connectors for broken, bent, pushed out, and corroded terminals. Repair as necessary.

No

Go to Test Step 4

Test Step 4 - VERIFY INTERMITTENT LOST COMMUNICATION DTC-OFFENDING MODULE

Turn the ignition on.

With the scan tool, select Network View and select Advanced.

Is there more than one ECU with stored DTCs "Logged Against" the module and NO lost communication DTCs stored in the offending module?

Yes

Check for TSB related to this offending module.

No

Go to Test Step 5

Test Step 5 - VERIFY INTERMITTENT LOST COMMUNICATION DTC-REPORTING MODULE

Turn the ignition on.

With the scan tool, select Network View and select Advanced.

Is there ONLY ONE ECU with stored DTCs "Logged Against" the module?

Yes

Check for TSB related to the module that set this DTC.

No

Verify if the vehicle was recently in for this type of service. Otherwise, visually inspect the related wiring harness for chafed, pierced, pinched and partially broken wires and the wiring harness connectors for broken, bent, pushed out and corroded terminals. Repair as necessary.