P31FF

Description

The ECM receives two vehicle speed signals via the CAN communication line. One is sent from "combination meter", and the other is from TCM (Transmission control module). The ECM uses these signals for ASCD control. Automatic Speed Control Device (ASCD) System Description for ASCD
functions.


DTC Logic


DTC DETECTION LOGIC

NOTE:
- If DTC P31FF is displayed with DTC UXXXX, first perform the trouble diagnosis for DTC UXXXX. Refer to
Testing and Inspection.
- If DTC P31FF is displayed with DTC P0A1D, first perform the trouble diagnosis for DTC P0A1D. Refer to
P0A1D.






DTC CONFIRMATION PROCEDURE


1. PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.
- GO TO 2.

2. PERFORM DTC CONFIRMATION PROCEDURE

1.Set the vehicle to READY.
2.Drive the vehicle at more than 40 km/h (25 MPH).

CAUTION:
Always drive the vehicle at a safe speed.
NOTE:
This procedure may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a road test is expected to be easier, it is unnecessary to lift the vehicle.
3.Check DTC.
Is DTC detected?
YES- Proceed to .
NO- INSPECTION END


Diagnosis Procedure


1. CHECK DTC WITH TCM

Check DTC with TCM. Scan Tool Testing and Procedures.
Is the inspection result normal?
YES- GO TO 2.
NO- Perform trouble diagnosis relevant to DTC indicated. Testing and Inspection.

2. CHECK DTC WITH ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)

Check DTC with ABS actuator and electric unit. Scan Tool Testing and Procedures.
Is the inspection result normal?
YES- GO TO 3.
NO- Perform trouble diagnosis relevant to DTC indicated. Testing and Inspection.

3. CHECK DTC WITH COMBINATION METER

Check DTC with combination meter. Combination Meter.
Is the inspection result normal?
YES- INSPECTION END
NO- Perform trouble diagnosis relevant to DTC indicated. Testing and Inspection.