Toyota Tacoma 2015-2018 Service Manual: Steering Pad Switch Circuit
DESCRIPTION
This circuit sends an operation signal from the steering pad switch assembly to the radio and display receiver assembly.
If there is an open in the circuit, the audio system cannot be operated using the steering pad switch assembly.
If there is a short in the circuit, the same condition as when a switch is continuously depressed occurs.
Therefore, the radio and display receiver assembly cannot be operated using the steering pad switch assembly, and also the radio and display receiver assembly itself cannot function.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
The vehicle is equipped with a Supplemental Restraint System (SRS) which includes
components such as airbags. Before servicing (including removal or installation
of parts), be sure to read the precautionary notice for the Supplemental Restraint
System (See page .gif)
).
PROCEDURE
|
1. |
CHECK HARNESS AND CONNECTOR (STEERING PAD SWITCH SIGNAL) |
|
(a) Disconnect the radio and display receiver assembly connector. |
|
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Switch Condition |
Specified Condition |
|---|---|---|
|
R31-21 (SW1) - R31-23 (SWG) |
No switch is pushed |
99 to 101 kΩ |
|
Volume+ is pushed |
1000 to 1020 Ω |
|
|
Volume- is pushed |
3178 to 3242 Ω |
|
|
Seek+ is pushed |
Below 2.5 Ω |
|
|
Seek- is pushed |
327 to 333 Ω |
|
|
R31-22 (SW2) - R31-23 (SWG) |
No switch is pushed |
99 to 101 kΩ |
|
MODE switch is pushed |
Below 2.5 Ω |
|
|
On Hook switch is pushed |
327 to 333 Ω |
|
|
Off Hook switch is pushed |
1000 to 1020 Ω |
|
|
Voice switch is pushed |
3178 to 3242 Ω |
|
*a |
Front view of wire harness connector (to Radio and Display Receiver Assembly) |
| OK | .gif) |
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
|
.gif)
|
2. |
INSPECT STEERING PAD SWITCH ASSEMBLY |
(a) Remove the steering pad switch assembly (See page
).
(b) Inspect the steering pad switch assembly (See page
).
| NG | |
REPLACE STEERING PAD SWITCH ASSEMBLY |
|
|
3. |
INSPECT SPIRAL CABLE WITH SENSOR SUB-ASSEMBLY |
(a) Remove the spiral cable with sensor sub-assembly (See page
).
(b) Inspect the spiral cable with sensor sub-assembly (See page
).
| OK | |
REPAIR OR REPLACE HARNESS OR CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - SPIRAL CABLE WITH SENSOR SUB-ASSEMBLY) |
| NG | |
REPLACE SPIRAL CABLE WITH SENSOR SUB-ASSEMBLY |
Vehicle Speed Signal Circuit between Radio Receiver and Combination Meter
DESCRIPTION
for Audio Function:
The radio and display receiver assembly receives a vehicle speed signal
from the combination meter assembly and sends the signal to radio and display
...
Illumination Circuit
DESCRIPTION
Power is supplied to the radio and display receiver assembly and steering pad
switch assembly illumination when the light control switch is in the TAIL or HEAD
position.
WIRING DIAGR ...
Other materials:
Open in Driver Side Electrical Antenna Circuit (B27A1)
DESCRIPTION
The certification ECU (smart key ECU assembly) generates a request signal and
transmits the signal to the front door outside handle assembly LH [electrical key
antenna] at intervals of 0.25 seconds. For the front door outside handle assembly
LH [electrical key antenna] to detect w ...
Problem Symptoms Table
PROBLEM SYMPTOMS TABLE
HINT:
Use the table below to help determine the cause of problem symptoms.
If multiple suspected areas are listed, the potential causes of the symptoms
are listed in order of probability in the "Suspected Area" column of the
table. Check each sy ...
Check Bus 2 Line for Short to +B
DESCRIPTION
There may be a short circuit between one of the CAN bus lines and +B when no
resistance exists between terminal 18 (CA4H) of the central gateway ECU (network
gateway ECU) and terminal 16 (BAT) of the DLC3, or terminal 17 (CA4L) of the central
gateway ECU (network gateway ECU) and ...