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. |
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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.
Precaution
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT
BELT PRE-TENSIONER"
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”,
used along
with a front seat belt, helps to reduce the risk or severity of injur ...
Satellite radio reception (if so equipped)
When the satellite radio is used for the first time
or the battery has been replaced, the satellite
radio may not work properly. This is not a malfunction.
Wait more than 10 minutes with satellite
radio ON and the vehicle outside of any metal or
large building for satellite radio to receive a ...
Parking brake switch
Component Function Check
1.CHECK PARKING BRAKE SWITCH OPERATION
Check that brake warning lamp in combination meter turns ON/OFF
when parking brake is actuated.
Is the inspection result normal?
YES >> Inspection End.
NO >> Proceed to diagnosis procedure. Refer to BRC-90, " ...