DTC B1178: F-CAN Communication Line Error DTC B1168: Gauge Control Module Lost Communication with ECM/PCM (Engine Messages) DTC B1169: Gauge Control Module Lost Communication with the PCM (A/T Messages) Clear the DTCs using the HDS. Turn the ignition switch OFF then back to the ON (II). Start and run the engine for at least 5 seconds then turn the engine off. Check for DTCs by selecting the DTCs MENU (DTCs) from the HDS. Is DTC B1178, B1168 and/or B1169 indicated?
YES | - | Go to Step 5 .
NO | - | Intermittent failure, the F-CAN communication line is OK at this time.■
Check for DTCs in the ECM/PCM. Are any DTCs indicated?
YES | - | Troubleshoot the ECM/PCM DTCs.■
NO | - | Go to Step 6 .
Perform the gauge control module input test. Are all inputs OK?
YES | - | Go to Step 7 .
NO | - | Repair the faulty input then recheck for DTCs.■
Substitute a known-good gauge control module. Clear the DTCs using HDS. Turn the ignition switch OFF then back to the ON (II). Start and run the engine for at least 5 seconds then turn the engine off. Check for DTCs by selecting the DTCs MENU (DTCs) from the HDS. Is DTC B1178, B1168 and/or B1169 indicated?
YES | - | Replace the ECM / PCM .■
NO | - | The original gauge control module is faulty; replace the gauge control module .■