Toyota Sienna Service Manual: Back-up Power Source Circuit
DESCRIPTION
This is the back-up power source for the A/C amplifier. Power is supplied even when the ignition switch is off and is used for diagnostic trouble code memory, etc.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT FUSE (ECU-B)
(a) Remove the ECU-B fuse from the engine room junction block.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance
2 CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - BATTERY)
(a) Disconnect the connector from the A/C amplifier.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
ACC Power Source Circuit
DESCRIPTION
This circuit supplies power to the A/C amplifier and the illumination for the
clock.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT FUSE (ECU ACC)
(a) Remove the ECU ACC fuse fr ...
Other materials:
A/F Sensor Circuit Slow Response
DTC P2A00 A/F Sensor Circuit Slow Response (Bank 1
Sensor 1)
DTC P2A03 A/F Sensor Circuit Slow Response (Bank 2
Sensor 1)
HINT:
DTC P2A00 indicates malfunctions related to the bank 1 A/F sensor.
DTC P2A03 indicates malfunctions related to the bank 2 A/F sensor.
Bank 1 r ...
Headlight leveling switch
ON-VEHICLE INSPECTION
1. HEADLIGHT LEVELING SWITCH
Connect the battery positive (+) lead to the terminal
1 and the battery negative (-) lead to the terminal 5.
Measure the resistance between the terminal 4 and
the battery negative (-) lead when headlight leveling
switch ...
Fail-safe chart
1. AUTO CANCEL FUNCTION (FAIL-SAFE FUNCTION):
HINT:
If a system malfunction occurs, the applicable DTCs will
appear on the multi-information display. In some cases,
a DTC will be set due to weather or vehicle operating
conditions, this does not indicate a system malfunction.
E3 (i ...
