Toyota Sienna Service Manual: Ignition Switch Circuit
DESCRIPTION
When the ignition switch is turned to the ON position, battery positive voltage is applied to terminal IG of the ECU. When battery positive voltage is applied to terminal IG of the ECU while the theft deterrent system is operating, the warning stops.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT FUSES (ECU-IG, AM1)
- Remove the ECU-IG and AM1 fuses from the instrument panel J/B.
- Measure the resistance.
Standard resistance: Below 1 Ω
2 INSPECT RELAY (IG1)
- Remove the IG1 relay from the instrument panel J/B.
- Check the operation of the IG1 relay.
Standard resistance
3 INSPECT IGNITION OR STARTER SWITCH ASSEMBLY
- Disconnect the I15 switch connector.
- Measure the resistance according to the value(s) in the table below.
Standard resistance
4 CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (POWER SOURCE)
- Disconnect the 1A J/B connector.
- Turn the ignition switch ON.
- Measure the voltage according to the value(s) in the table below.
Standard voltage
REPLACE INSTRUMENT PANEL J/B ASSEMBLY
Security Horn Circuit
DESCRIPTION
During the alarm sounding state, the relay in the ECU turns on and off in a
cycle of approximately 0.2
seconds, causing the security horn to sound.
WIRING DIAGRAM
INSPECTION PROC ...
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 ...
Other materials:
Diagnostic trouble code chart
HINT:
If a trouble code is displayed during the DTC check, check
the circuit indicated by the DTC. For details of each code,
turn to the page for the respective DTC Code. in the DTC
chart.
Inspect the fuse and relay before investigating the trouble
areas as shown in the table below.
...
Approach warning
When your vehicle is too close to a vehicle ahead, and sufficient automatic
deceleration via the cruise control is not possible, the display
will flash and the buzzer will sound to alert the driver. An example of
this would be if another driver cuts in front of you while you are following
a vehi ...
On-vehicle inspection
1. INSPECT THROTTLE BODY
Listen to the throttle control motor operating sounds.
Turn the ignition switch to the ON position.
When pressing the accelerator pedal position
sensor lever, listen to the running motor. Make
sure that no friction noise comes from the
motor.
...
