Toyota Sienna Service Manual: ECU Power Source Circuit
DESCRIPTION
This circuit provides power to operate the theft deterrent (warning) ECU.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT FUSE (ECU-B)
- Remove the ECU-B fuse from the engine room J/B.
- Measure the resistance.
Standard resistance: Below 1 Ω
2 CHECK INSTRUMENT PANEL J/B ASSEMBLY (POWER SOURCE)
- Disconnect the 1C J/B connector.
- Measure the voltage according to the value(s) in the table below.
Standard voltage
3 CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL J/B ASSEMBLY - BODY GROUND)
- Disconnect the 1K and 1L J/B connector.
- Measure the resistance according to the value(s) in the table below.
Standard resistance
REPLACE INSTRUMENT PANEL J/B ASSEMBLY
Security Indicator Light Circuit
DESCRIPTION
Even when the theft deterrent system is in the disarmed state, the security
indicator blinks due to a signal
output from the immobiliser system. The security indicator blinks continuou ...
Engine hood courtesy
switch
Inspection
1. INSPECT ENGINE HOOD COURTESY SWITCH
Measure the resistance according to the value(s) in
the table below.
Standard resistance
If the result is not as specified, r ...
Other materials:
Throttle / Pedal Position Sensor / Switch "A" Circuit Range / Performance
Problem
HINT:
This DTC relates to the Throttle Position (TP) sensor.
DESCRIPTION
Refer to DTC P0120 (See page ES-145).
MONITOR DESCRIPTION
The ECM uses the TP sensor to monitor the throttle valve opening angle.
This sensor transmits two signals: VTA1 and VTA2. VTA1 is used to detect the
th ...
Diagnosis system
1. CHECK DLC3
The vehicle's ECU uses ISO 15765-4 for
communication protocol. The terminal arrangement
of the DLC3 complies with SAE J1962 and matches
the ISO 15765-4 format
NOTICE:
*: Before measuring the resistance, leave the
vehicle as is for at least 1 minute and do not
oper ...
Shifting the shift lever
While the engine switch is in the
“ON” position (vehicles without a
smart key system) or IGNITION ON mode (vehicles with a smart
key system), move the shift lever with the brake pedal
depressed.
When shifting the shift lever between P and D, make sure that the vehicle
is completely ...
