DTC Troubleshooting: 86-31

DTC 86-31:  F-CAN Communication with Gauge Control Module Malfunction

1.Turn the ignition switch ON (II).

2.Clear the DTC with the HDS.

3.Turn the ignition switch OFF, then turn it ON (II) again.

4.Check for DTCs with the HDS.

Is 86-31 DTC indicated?

YES - Go to 5.

NO - Intermittent failure, the system is OK at this time. Check for loose terminals between the ECM/PCM connector A (44P), the gauge control module (tach) connector (36P) and the ABS modulator-control unit 25P connector. Refer to intermittent failures troubleshooting.n

5.Turn the ignition switch ON (II).

Do the gauge indicators come on?

YES - Go to 6.

NO - Do the gauge control module troubleshooting.n

6.Turn the ignition switch OFF.

7.Disconnect the gauge control module (tach) connector (36P).

8.Disconnect the ABS modulator-control unit 25P connector.

9.Check for continuity between ABS modulator-control unit 25P connector terminal and gauge control module (tach) connector (36P) terminal (see table).

Sign Connector Terminal No. 
ABS Modulator-control Unit Gauge Control Module 
CAN-L 17 19 


Is there continuity?

YES - Check for loose terminals in the gauge control module (tach) connector (36P). If necessary, substitute a known-good gauge control module (tach), then go to 1 and recheck. If no DTCs are indicated, replace the original gauge control module (tach). If DTC 86-31 resets, replace the ABS modulator-control unit: Except K20Z2 engine model, K20Z2 engine model.n

NO - Repair open in the wire between the gauge control module (tach) and the ABS modulator-control unit.n