Toyota Tacoma (2015-2018) Service Manual: Microphone Circuit between Microphone and Radio Receiver

Toyota Tacoma (2015-2018) Service Manual / Navigation / Multi Info Display / Navigation System / Microphone Circuit between Microphone and Radio Receiver

DESCRIPTION

The navigation receiver assembly and telephone microphone assembly are connected to each other using the microphone connection detection signal lines.

Using this circuit, the navigation receiver assembly sends power to the telephone microphone assembly and the telephone microphone assembly sends microphone signals to the navigation receiver assembly.

WIRING DIAGRAM

PROCEDURE

1.	CHECK MICROPHONE

(a) Enter the "Microphone Check" screen. Refer to Check Microphone in Operation Check (See page ).

(b) When a voice is input into the microphone, check that the microphone input level meter changes according to the input voice.

OK:

Check result is normal.

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

2.	CHECK HARNESS AND CONNECTOR (NAVIGATION RECEIVER ASSEMBLY - TELEPHONE MICROPHONE ASSEMBLY)

(a) Disconnect the N25 navigation receiver assembly connector.

(b) Disconnect the T26 telephone microphone assembly connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
N25-4 (MACC) - T26-1 (MACC)	Always	Below 1 Ω
N25-5 (MIN+) - T26-2 (MIC+)	Always	Below 1 Ω
N25-19 (MIN-) - T26-4 (MIC-)	Always	Below 1 Ω
N25-6 (SNS2) - T26-3 (SNS2)	Always	Below 1 Ω
N25-4 (MACC) - Body ground	Always	10 kΩ or higher
N25-5 (MIN+) - Body ground	Always	10 kΩ or higher
N25-19 (MIN-) - Body ground	Always	10 kΩ or higher
N25-18 (SGND) - Body ground	Always	10 kΩ or higher
N25-6 (SNS2) - Body ground	Always	10 kΩ or higher

(d) Reconnect the navigation receiver assembly connector.

(e) Reconnect the telephone microphone assembly connector.

REPAIR OR REPLACE HARNESS OR CONNECTOR

3.	INSPECT NAVIGATION RECEIVER ASSEMBLY

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

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
N25-4 (MACC) - Body ground	Ignition switch ACC	4 to 6 V

*a	Component with harness connected (Navigation Receiver Assembly)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
N25-19 (MIN-) - Body ground	Always	Below 1 Ω
N25-18 (SGND) - Body ground	Always	Below 1 Ω

REPLACE NAVIGATION RECEIVER ASSEMBLY

4.	INSPECT TELEPHONE MICROPHONE ASSEMBLY

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

*a	Component without harness connected (Telephone Microphone Assembly)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
3 (SNS2) - 4 (MIC-)	Always	Below 1 Ω

REPLACE TELEPHONE MICROPHONE ASSEMBLY

5.	INSPECT TELEPHONE MICROPHONE ASSEMBLY

(a) Turn the ignition switch to ACC.

*a	Component with harness connected (Telephone Microphone Assembly)

(b) Connect an oscilloscope to terminals 2 (MIC+) and 4 (MIC-) of the telephone microphone assembly connector.

Result

Result	Proceed to
A waveform synchronized with the voice input to the telephone microphone assembly is output	A
A waveform synchronized with the voice input to the telephone microphone assembly is not output	B

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

REPLACE TELEPHONE MICROPHONE ASSEMBLY

Vehicle Speed Signal Circuit between Stereo Component Amplifier and Combination Meter

DESCRIPTION The stereo component amplifier assembly receives a vehicle speed signal from the combination meter assembly to control the ASL function. HINT: A voltage of 12 V or 5 V is outp ...

Radio Receiver Power Source Circuit

DESCRIPTION This is the power source circuit to operate the navigation receiver assembly. WIRING DIAGRAM CAUTION / NOTICE / HINT NOTICE: Inspect the fuses for circuits related to this s ...

Other materials:

Removal
REMOVAL CAUTION / NOTICE / HINT HINT: Use the same procedure for the LH side and RH side. The following procedure listed is for the LH side. PROCEDURE 1. REMOVE FRONT WHEEL 2. DRAIN BRAKE FLUID NOTICE: Immediately wash off any brake fluid that comes into contact with any pa ...

Center Airbag Sensor Assembly Malfunction (B1000/31)
DESCRIPTION The airbag sensor assembly consists of a deceleration sensor, safing sensor, drive circuit, diagnosis circuit, ignition control, etc. If the airbag sensor assembly receives signals from the deceleration sensor, it determines whether or not the SRS should be activated. DTC B1000/31 ...

Main Switch Signal Circuit
DESCRIPTION When the wireless charger main switch (mobile wireless charger switch) is turned on, this circuit sends an on signal to the mobile wireless charger cradle assembly using the power supplied to the wireless charger main switch (mobile wireless charger switch). WIRING DIAGRAM CAU ...