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.
Precaution for work
When removing or disassembling each component, be careful not to damage
or deform it. If a component
may be subject to interference, be sure to protect it with a shop cloth.
When removing (disengaging) components with a screwdriver or similar
tool, be sure to wrap the component
with a ...
Additional service when replacing ecm
Description
When replacing ECM, the following procedure must be performed. (For details,
refer to EC-135, "Work Procedure".)
PROGRAMMING OPERATION
NOTE:
After replacing with a blank ECM, programming is required to write ECM
information. Be sure to follow the procedure
to perform t ...
Loading tips
The GVW must not exceed GVWR
or GAWR as specified on the
F.M.V.S.S./C.M.V.S.S. certification
label.
Do not load the front and rear axle to
the GAWR. Doing so will exceed the
GVWR.
WARNING
Properly secure all cargo with
ropes or straps to help prevent it
from slid ...