Toyota Sequoia (2005). Manual - part 567

I28299

TX–

Radio and Navigation Assy
Wire Harness View:

TX+

R27

I28337

TX+

R24

TX–

Rear Seat Audio Controller
Wire Harness View:

–

DIAGNOSTICS

REAR SEAT AUDIO SYSTEM

DI–2063

2257

2

Check harness and connector (Rear seat audio controller – Radio and navigation
assy).

PREPARATION:
Disconnect the R24 and R27 connectors.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:

Symbol 

(Tester connection)

Condition

Specified condition

TX+ (R24–22) – 

TX+ (R27–9)

Always

Below 1 

Ω

TX– (R24–23) – 

TX– (R27–10)

Always

Below 1 

Ω

TX+ (R24–22) – Body

ground

Always

10 k

Ω 

or higher

TX– (R24–23) – Body

ground

Always

10 k

Ω 

or higher

NG

Repair or replace harness or connector.

OK

Replace rear seat audio controller.

I28605

TX1+

R19

Radio Receiver Assy
Wire Harness View:

TX1–

I28337

TX+

R24

TX–

Rear Seat Audio Controller
Wire Harness View:

DI–2064

–

DIAGNOSTICS

REAR SEAT AUDIO SYSTEM

2258

3

Check harness and connector (Rear seat audio controller – Radio receiver assy).

PREPARATION:
Disconnect the R19 and R24 connectors.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:

Symbol 

(Tester connection)

Condition

Specified condition

TX+ (R24–22) – 

TX1+ (R19–9)

Always

Below 1 

Ω

TX– (R24–23) – 

TX1– (R19–10)

Always

Below 1 

Ω

TX+ (R24–22) – Body

ground

Always

10 k

Ω 

or higher

TX– (R24–23) – Body

ground

Always

10 k

Ω 

or higher

NG

Repair or replace harness or connector.

OK

Replace rear seat audio controller.

I28606

Radio Receiver Assy
Wire Harness View:

TX–

TX+

R4

I28292

TX+

Radio and Navigation Assy:

TX–

R30

I28752

Stereo Component Amplifier Assy :

S10

TX–

TX+

–

DIAGNOSTICS

REAR SEAT AUDIO SYSTEM

DI–2065

2259

4

Check harness and connector (Radio receiver assy / radio and navigation assy –
Stereo component amplifier assy).

PREPARATION:
Disconnect the radio receiver assy or radio and navigation assy
and stereo component amplifier assy connectors.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:
Radio Receiver Assy:

Symbol 

(Tester connection)

Condition

Specified condition

TX+ (R4–5) – 

TX+ (S10–20)

Always

Below 1 

Ω

TX– (R4–15) – 

TX– (S10–19)

Always

Below 1 

Ω

TX+ (R4–5) – Body

ground

Always

10 k

Ω 

or higher

TX– (R4–15) – Body

ground

Always

10 k

Ω 

or higher

Radio And Navigation Assy:

Symbol 

(Tester connection)

Condition

Specified condition

TX+ (R30–5) – 

TX+ (S10–20)

Always

Below 1 

Ω

TX– (R30–15) – 

TX– (S10–19)

Always

Below 1 

Ω

TX+ (R30–5) – Body

ground

Always

10 k

Ω 

or higher

TX– (R30–15) – Body

ground

Always

10 k

Ω 

or higher

NG

Repair or replace harness or connector.

OK

Replace rear seat audio controller.

I28377

w/o Navigation System:

R19
Radio Receiver Assy

Rear Seat Audio Controller

RMUT

ID2

19

R24

11

RMU

11

LG

R–W

I28377

w/ Navigation System:

R27
Radio and Navigation Assy

Rear Seat Audio Controller

RMUT

ID2

19

R24

11

RMUT

11

LG

R–W

DI–2066

–

DIAGNOSTICS

REAR SEAT AUDIO SYSTEM

2260

Mute signal circuit (to rear seat audio controller)

CIRCUIT DESCRIPTION

This circuit sends the signal to the rear seat audio controller to mute the noise. Because of that, the noise
produced by changing the sound source ceases.
If there is an open in the circuit, noise can be heard from the speaker when changing the sound source.
If there is a short in the circuit, even though the rear seat audio controller is normal, no sound or only extreme-
ly small sound can be produced.

WIRING DIAGRAM

DIDAO–01