DTC B1168: Gauge Control Module Lost Communication with PCM (ENG Message); DTC B1169: Gauge Control Module Lost Communication with the PCM (A/T Message); DTC B1178: F-CAN Communication Error

Clear the DTCs with the HDS.
Turn the ignition switch OFF, and then back ON (II).
Wait for 6 seconds or more.
Check for DTCs with the HDS.
Is DTC B1168, B1169, and/or B1178 indicated?

YES - Go to step 5.

NO - Intermittent failure, the system is OK at this time. Check for loose or poor connection between the gauge control module and the PCM.
Check for Fuel and Emissions Systems DTCs with the HDS.
Are there any DTCs indicated?

YES - Go to the indicated DTCs troubleshooting, then recheck.

NO - Go to step 6.
Turn the ignition switch OFF.
Disconnect gauge control module connector B (28P).
Jump the SCS with the HDS.
Disconnect PCM connector A (49P).
Connect gauge control module connector B (28P) No. 15 and No. 16 terminals and body ground with jumper wires.

Fig 1: Connecting Gauge Control Module Connector B No. 15 And No. 16 Terminals And Body Ground With Jumper Wires
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Check for continuity between body ground and PCM connector terminals E15 and E26 individually.

Fig 2: Checking Continuity Between Body Ground And PCM Connector Terminals E15 And E26
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Update the PCM if it does not have the latest software (see UPDATING THE PCM ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), and recheck. If the indication goes away, replace the original PCM (see PCM REPLACEMENT ). If the DTC is still present, replace the gauge control module (see GAUGE CONTROL MODULE REPLACEMENT ).

NO - Repair an open in the wire.