DTC 85: F-CAN Communication Error

WARNING: This page is about a different car, the 2008 Honda Fit. However, it is still accessible from the selected car via links, so may be relevant.

Turn the ignition switch ON (II).
Check for DTCs in the ECM/PCM with the HDS.
Are there any DTCs indicated?

YES - Go to the indicated ECM/PCM troubleshooting.

NO - Go to step 3.
Clear the DTC with the HDS.
Turn the ignition switch OFF, then turn the ignition switch ON (II) again.
Wait about 5 seconds.
Check for DTCs with the HDS.
Is DTC 85 indicated?

YES - Go to step 7.

NO - The system is OK at this time.
Test-drive the vehicle.
Does the speedometer work?

YES - Go to step 11.

NO - Go to step 8.
Turn the ignition switch OFF.
Disconnect the TPMS control unit 20P connector.
Test-drive the vehicle.
Does the speedometer work?

YES - Check for loose terminals and poor connections at the TPMS control unit. If necessary, substitute a known-good TPMS control unit (see TPMS CONTROL UNIT REPLACEMENT ), and recheck.

NO - Substitute a known-good ECM/PCM and recheck.
Turn the ignition switch OFF.
Short the SCS line with the HDS.
Disconnect ECM/PCM connector E (31P).
Disconnect the TPMS control unit 20P connector.

Check for continuity between the TPMS control unit 20P connector terminals and ECM/PCM connector E (31P) terminals individually, (see table).

CONNECTOR TERMINAL REFERENCE

Terminal name	TPMS control unit terminal	ECM/PCM E terminal
CANL	No. 11	No. 24
CANH	No. 1	No. 11

Fig 1: Checking Continuity Between TPMS Control Unit 20P Connector Terminals And ECM/PCM Connector E (31P) Terminals

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES - Check for loose terminals and poor connections at the TPMS control unit. If necessary, substitute a known-good TPMS control unit (see TPMS CONTROL UNIT REPLACEMENT ), and recheck.

NO - Repair open in the wire between TPMS control unit and the ECM/PCM.