Toyota Sienna Service Manual: Illumination Circuit
DESCRIPTION
Power is supplied to the radio and navigation assembly and steering pad switch illumination when the light control switch is in the TAIL or HEAD position.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE: The vehicle is equipped with an SRS (Supplemental Restraint System) such as the airbags. Before servicing (including removal or installation of parts), be sure to read the precautionary notice for the Supplemental Restraint System
1 CHECK ILLUMINATION
- Check if the illumination for the radio and navigation assembly, steering pad switch, glove box or others (Hazard switch, cigarette lighter, etc.) comes on when the light control switch is turned to the HEAD or TAIL position.
Result
2 CHECK HARNESS AND CONNECTOR (BATTERY - SPIRAL CABLE SUB-ASSEMBLY)
- Disconnect the spiral cable sub-assembly connector.
- Measure the voltage according to the value(s) in the table below.
Standard voltage
3 CHECK STEERING PAD SWITCH ASSEMBLY
- Disconnect the steering pad switch assembly connector.
- Disconnect the steering pad switch connector.
- Connect the positive (+) lead to terminal ILL+ and the negative (-) lead to terminal EAU of the steering pad switch connector.
- Check if the illumination for the steering pad switch comes on.
4 INSPECT SPIRAL CABLE SUB-ASSEMBLY
- Disconnect the steering pad switch and spiral cable subassembly connectors.
- Measure the resistance according to the value(s) in the table below.
Standard resistance
NOTICE: The spiral cable is an important part of the SRS airbag system. Incorrect removal or installation of the spiral cable may prevent the airbag from deploying. Be sure to read the page shown in the brackets
5 CHECK HARNESS AND CONNECTOR (SPIRAL CABLE SUB-ASSEMBLY - RADIO AND NAVIGATION ASSEMBLY)
- Disconnect the connectors from the radio and navigation assembly and spiral cable sub-assembly.
- Measure the resistance according to the value(s) in the table below.
Standard resistance
REPLACE RADIO AND NAVIGATION ASSEMBLY
6 INSPECT STEERING PAD SWITCH CABLE
- Disconnect the steering pad switch LH and the steering pad switch RH.
- Measure the resistance according to the value(s) in the table below
Standard resistance
REPLACE STEERING PAD SWITCH RH
7 CHECK HARNESS AND CONNECTOR (BATTERY - RADIO AND NAVIGATION ASSEMBLY)
- Disconnect the radio and navigation assembly connector R15.
- Measure the voltage according to the value(s) in the table below.
Standard voltage
8 CHECK HARNESS AND CONNECTOR (RADIO AND NAVIGATION ASSEMBLY - COMBINATION METER)
- Disconnect the radio and navigation assembly and combination meter connectors.
- Measure the resistance according to the value(s) in the table below.
Standard voltage
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
Steering Pad Switch Circuit
DESCRIPTION
This circuit sends an operation signal from the steering pad switch to the
radio receiver.
If there is an open in the circuit, the navigation system cannot be operated
using the st ...
Parking Brake Switch Circuit
DESCRIPTION
This circuit is from the parking brake switch to the radio and navigation
assembly.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 CHECK BRAKE WARNING LIGHT
Check that the brake warni ...
Other materials:
Speaker Circuit
DESCRIPTION
When the vehicle has a built-in type amplifier, a sound signal is
sent from the radio receiver to the
speakers via the "6 Speaker System" circuit.
When the vehicle has a separate type amplifier, a sound signal
from the radio receiver is amplified by
...
Short to GND in Side Squib RH Circuit
DTC B0112/41 Short to GND in Side Squib RH Circuit
DESCRIPTION
The side squib RH circuit consists of the center airbag sensor assembly and
the front seat side airbag
assembly RH.
The circuit instructs the SRS to deploy when deployment conditions are met.
DTC B0112/41 is recorded when a sh ...
Problem symptoms table
Vehicle stability control system:
TERMINALS OF ECU
1. Terminal of ECU
(*1): Models with dynamic laser cruise control
(*2): 2WD model
2. Terminal Inspection
(a) Disconnect the connector and measure the voltage or resistance on the wire harness side.
HINT: Voltage cannot be measured wit ...
