Toyota 4Runner manuals

Toyota 4Runner: Microphone Circuit between Microphone and Radio Receiver

Toyota 4Runner Service Manual / Audio / Visual / Telematics / Audio / Video / Audio And Visual System / Microphone Circuit between Microphone and Radio Receiver

DESCRIPTION

  • The radio and display receiver assembly and map light assembly (telephone microphone assembly) are connected to each other using the microphone connection detection signal lines.
  • Using this circuit, the radio and display receiver assembly sends power to the map light assembly (telephone microphone assembly), and the map light assembly (telephone microphone assembly) sends microphone signals to the radio and display receiver assembly.

WIRING DIAGRAM


PROCEDURE

1.

CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY))

(a) Disconnect the G49 radio and display receiver assembly connector.

(b) Disconnect the U2 map light assembly (telephone microphone assembly) connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

G49-4 (MACC) - U2-14 (MACC)

Always

Below 1 Ω

G49-5 (MIN+) - U2-13 (MCO+)

Always

Below 1 Ω

G49-6 (SNS2) - U2-15 (SNS2)

Always

Below 1 Ω

G49-19 (MIN-) - U2-12 (MCO-)

Always

Below 1 Ω

G49-4 (MACC) - Body ground

Always

10 kΩ or higher

G49-5 (MIN+) - Body ground

Always

10 kΩ or higher

G49-6 (SNS2) - Body ground

Always

10 kΩ or higher

G49-18 (SGND) - Body ground

Always

10 kΩ or higher

G49-19 (MIN-) - Body ground

Always

10 kΩ or higher


NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

2.

INSPECT RADIO AND DISPLAY RECEIVER ASSEMBLY

(a) Reconnect the G49 radio and display receiver assembly connector.

(b) Reconnect the U2 map light assembly (telephone microphone assembly) connector.

(c) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

G49-4 (MACC) - Body ground

Ignition switch ACC

4 to 6 V


(d) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

G49-18 (SGND) - Body ground

Always

Below 1 Ω

G49-19 (MIN-) - Body ground

Always

Below 1 Ω

Text in Illustration

*a

Component with harness connected

(Radio and Display Receiver Assembly)


NG

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY

OK

3.

INSPECT MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY)

(a) Disconnect the U2 map light assembly (telephone microphone assembly) connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

U2-15 (SNS2) - U2-12 (MCO-)

Always

Below 1 Ω

Text in Illustration

*a

Component without harness connected

(Map Light Assembly (Telephone Microphone Assembly))



NG

GO TO STEP 5

OK

4.

INSPECT MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY)

(a) Reconnect the G49 radio and display receiver assembly connector.

(b) Reconnect the U2 map light assembly (telephone microphone assembly) connector.

(c) Turn the ignition switch to ACC.

(d) Connect an oscilloscope to terminals 13 (MCO+) and 12 (MCO-) of the U2 map light assembly (telephone microphone assembly) connector.

Text in Illustration

*a

Component with harness connected

(Map Light Assembly (Telephone Microphone Assembly))


(e) Check the waveform of the telephone microphone assembly using the oscilloscope.

Result

Proceed to

A waveform synchronized with the voice input to the map light assembly (telephone microphone assembly) is output

A

A waveform synchronized with the voice input to the map light assembly (telephone microphone assembly) is not output

B


A

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

B

5.

REPLACE TELEPHONE MICROPHONE ASSEMBLY

(a) Replace the telephone microphone assembly (See page ).


(b) Check if the same malfunction recurs.

Result

Proceed to

Malfunction does not recur

(returns to normal)

A

Malfunction recurs

B


A

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE


B

REPLACE MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY)

Reverse Signal Circuit
DESCRIPTION The radio and display receiver assembly receives a reverse signal from the park/neutral position switch assembly. WIRING DIAGRAM PROCEDURE 1. CHECK HARNESS A ...

Radio Receiver Power Source Circuit
DESCRIPTION This is the power source circuit to operate the radio and display receiver assembly. WIRING DIAGRAM CAUTION / NOTICE / HINT NOTICE: Inspect the fuses for circuits related to this sy ...

Other materials about Toyota 4Runner:

Inspection
INSPECTION PROCEDURE 1. INSPECT SHIFT SOLENOID VALVE SR (a) Measure the resistance according to the value(s) in the table below. Standard Resistance: Tester Connection Condition Specified Condition Shif ...

Sound Signal Circuit between Radio Receiver and Stereo Jack Adapter
DESCRIPTION The No. 1 stereo jack adapter assembly sends the sound signal from an external device to the radio and display receiver assembly via this circuit. The sound signal that has been sent is amplified by the radio and display receiver assembly and ...

© 2016-2019 | www.to4runner.net

0.0055