Toyota Sienna Service Manual: Diagnosis system
1. DIAGNOSIS FUNCTION
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- The diagnosis function makes the light and the
multi-information display come on, and the CRUISE
main indicator light blink as shown in the illustration.
When a malfunction occurs in the dynamic laser
cruise control system, the DTCs are stored in the
ECM.
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NOTICE:
- The master warning light goes off if the
system returns to normal condition.
- Since the stored data in the ECM is erased by
disconnecting the EFI and ETCS fuses or the
battery terminal, do not disconnect them until
the inspection has been completed.
2. DESCRIPTION
- The ECM controls the dynamic laser cruise control
system of the vehicle. The data and DTCs relating
to the dynamic laser cruise control system can be
read from the DLC3 of the vehicle. If the CRUISE
main indicator light does not come on after the DTC
check, there may be a problem with either the
combination meter or the CAN communication and
multiplex communication systems. Use the
intelligent tester to check and solve the problem.
3. CHECK DLC3
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- The vehicle's ECM uses the ISO 15765-4 for
communication protocol. The terminal arrangement
of the DLC3 complies with SAE J1962 and matches
the ISO 15765-4 format.
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NOTICE:
*: Before measuring the resistance, leave the
vehicle for at least 1 minute and do not operate
the ignition switch, any other switches, or
doors.
If the result is not as specified, the DLC3 may have
a malfunction. Repair or replace the harness and
connector.
Connect the cable of the intelligent tester to the
DLC3, turn the ignition switch to the ON position
and attempt to use the tester. If the display indicates
that a communication error has occurred, there is a
problem either with the vehicle or with the tester.
- If communication is normal when the tester is
connected to another vehicle, inspect the DLC3
of the original vehicle.
- If communication is still not possible when the
tester is connected to another vehicle, the
problem may be in the tester itself. Consult the
Service Department listed in the tester's
instruction manual.
4. CHECK INDICATOR
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- Turn the ignition switch to the ON position.
- Check that the CRUISE main indicator light and
READY indicator light come on when the cruise
control main switch is turned on, and that the
indicator lights go off when the main switch is turned
off.
HINT:
- If the indicator check result shows a problem,
proceed to troubleshooting for the combination
meter section.
- If a malfunction occurs in the vehicle speed
sensors, the stop light switch, or other related
parts during cruise control driving, the ECU
actuates AUTO CANCEL of the cruise control
and blinks the CRUISE main indicator light. This
indicator light informs the driver of the
malfunction. At the same time, the malfunction is
stored as a diagnostic trouble code.
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1. CHECK DISTANCE CONTROL ECU
Reference: waveform 1
HINT:
Terminal: LRDD - SGND
Gauge set: 2 V/DIV., 10 ms./DIV.
Condition: ignition switch in the ON posit ...
1. CHECK DTC
Connect the intelligent tester to the DLC3.
Connect the intelligent tester to the Controller
Area Network Vehicle Interface Module (CAN
VIM). Then connect th ...
Other materials:
Front Occupant Classification Sensor LH Collision
Detection
DTC B1785 Front Occupant Classification Sensor LH Collision
Detection
DESCRIPTION
DTC B1785 is output when the occupant classification ECU receives a collision
detection signal sent by
the front occupant classification sensor LH if an accident occurs.
DTC B1785 is also output when the front ...
Short to B+ in Side Squib LH Circuit
DTC B0118/46 Short to B+ in Side Squib LH Circuit
DESCRIPTION
The side squib LH circuit consists of the center airbag sensor assembly and
the front seat side airbag
assembly LH (side squib LH).
This circuit instructs the SRS to deploy when deployment conditions are met.
DTC B0118/46 is re ...
Diagnosis system
1. DESCRIPTION
Front power seat control system data can be read
through the Data Link Connector 3 (DLC3) of the
vehicle. When the system seems to be
malfunctioning, use the intelligent tester to check for
malfunctions and perform repairs.
2. CHECK DLC3
The vehicle us ...