Description
The ECM receives two vehicle speed sensor signals via 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. Refer to EC-51, "AUTOMATIC SPEED CONTROL DEVICE (ASCD) : System Description" for ASCD functions.
DTC Logic
DTC DETECTION LOGIC
NOTE:
DTC No. | CONSULT screen terms (Trouble diagnosis content) | DTC detecting condition | Possible cause |
P1574 | ASCD VHL SPD SEN (ASCD VHL SPD SEN) | ECM detects a difference between two vehicle speed signals is out of the specified range. |
|
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
CAUTION:
Always drive 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.
Is DTC detected? YES >> Proceed to EC-397, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
1.CHECK DTC WITH TCM
Check DTC with TCM. Refer to TM-108, "CONSULT Function".
Is DTC detected?
NO >> GO TO 2.
YES >> Perform trouble shooting relevant to DTC indicated.
2.CHECK DTC WITH “ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)”
Check DTC with ABS actuator and electric unit (control unit). Refer to BRC-31, "CONSULT Function (ABS)".
Is DTC detected? NO >> INSPECTION END
YES >> Perform trouble shooting relevant to DTC indicated.
Hvac branch line circuit
Diagnosis procedure
1.Check connector
Turn the ignition switch off.
Disconnect the battery cable from the negative terminal.
Check the terminals and connectors of the a/c auto amp. For damage, bend
and loose connection (unit
side and connector side).
Is the inspection result normal? ...
Inspection and adjustment
Additional service when replacing control unit
Additional service when replacing control unit : description
Memory reset procedure
Please observe the following instructions at confirming the moonroof
operation.
Note:
Do not disconnect the electronic power while the moonroof is operating ...
Fog light switch (if so equipped)
To turn the fog lights on, turn the headlight switch
to the position, then turn the
fog light
switch to the position.
If the headlight switch is in the AUTO position
and the fog light switch is moved to the ON
position, both the fog lights and the headlights
(including all other ...