SFI System

FA20 ENGINE CONTROL: SFI SYSTEM: U0073, U0101, U0122, U0140, U0155, U0402, U0416, U0423; Control Module Communication Bus "A" Off; 2013 MY FR-S [03/2012 -]
U0073 - Control Module Communication Bus "A" Off
U0101 - Lost Communication with TCM
U0122 - Lost Communication with Vehicle Dynamics Control Module
U0140 - Lost Communication with Body Control Module
U0155 - Lost Communication with Instrument Panel Cluster (IPC) Control Module
U0402 - Invalid Data Received from TCM
U0416 - Invalid Data Received from Vehicle Dynamics Control Module
U0423 - Invalid Data Received from Instrument Panel Cluster Control Module

DESCRIPTION

Refer to CAN communication system for system description System Description.





MONITOR DESCRIPTION

The ECM, TCM, skid control ECU (brake actuator assembly) and combination meter assembly communicate with each other via the CAN communication line. If there is a problem in this communication, the ECM stores the DTC.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS

All





U0073





U0101





U0122





U0155





U0402





U0416





U0423





TYPICAL MALFUNCTION THRESHOLDS

U0073





U0101





U0122





U0155





U0402





U0416





U0423





INSPECTION PROCEDURE

Go to CAN communication system for troubleshooting How to Proceed With Troubleshooting.

HINT
* When DTCs indicating a CAN communication system malfunction are output, repair the CAN communication system before repairing each corresponding sensor.
* Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
* If the CAN communication malfunctions, there is no data output from the ECM. In this case, some of the freeze frame data are not correct and not identical with the ECM data, but the ECM data are correct.

PROCEDURE

1. CHECK ANY OTHER DTCS OUTPUT

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine / Trouble Codes.

(e) Read the DTCs.

Result:





B -- GO TO DTC CHART SFI System

A -- GO TO CAN COMMUNICATION SYSTEM How to Proceed With Troubleshooting