Toyota CH-R Service Manual: Telephone Microphone Error (B1572)

Toyota CH-R Service Manual / Cellular Communication / Safety Connect System / Telephone Microphone Error (B1572)

DESCRIPTION

This DTC is set when the DCM (Telematics Transceiver) detects a malfunction in the telephone microphone assembly circuit.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B1572

Telephone Microphone Error

Current of MCVD reaches malfunction criteria for 10 seconds while ignition switch is ON.
  • Wire harness or connector
  • Map light assembly (Telephone microphone assembly)
  • DCM (Telematics Transceiver)

WIRING DIAGRAM

CAUTION / NOTICE / HINT

HINT:

Before performing this diagnostic procedure, make sure to perform Health Check and confirm that the DCM/VIN registration information is correct.

Click here

PROCEDURE

1.

CHECK DTC

(a) Turn the ignition switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the ignition switch ON and wait for 10 seconds.

(d) Turn the Techstream on.

(e) Clear the DTCs.

Body Electrical > Telematics > Clear DTCs

(f) Recheck for DTCs.

Body Electrical > Telematics > Trouble Codes

Result

Proceed to

DTC B1572 is output

A

DTC B1572 is not output

B
B

CHECK FOR INTERMITTENT PROBLEMS

A

2.

INSPECT MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY POWER SOURCE)

(a) Remove the map light assembly (telephone microphone assembly) but do not disconnect the connectors.

Click here

*a

Component with harness connected

(Map Light Assembly (Telephone Microphone Assembly))

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

R2-9 (MACC) - Body ground

Ignition switch ACC

4 to 6 V

Standard Resistance:

Tester Connection

Condition

Specified Condition

R2-7 (MCO-) - Body ground

Always

Below 1 Ω
NG

GO TO STEP 4

OK

3.

CHECK HARNESS AND CONNECTOR (DCM (TELEMATICS TRANSCEIVER) - MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY))

(a) Disconnect the F134 DCM (Telematics Transceiver) connector.

(b) Disconnect the R2 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

F134-34 (MIC+) - R2-8 (MCO+)

Always

Below 1 Ω

F134-34 (MIC+) or R2-8 (MCO+) - Body ground

Always

10 kΩ or higher

F134-35 (MIC-) - R2-7 (MCO-)

Always

Below 1 Ω

F134-35 (MIC-) or R2-7 (MCO-) - Body ground

Always

10 kΩ or higher

F134-32 (SGND) - Body ground

Always

10 kΩ or higher
OK

REPLACE MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.

INSPECT DCM (TELEMATICS TRANSCEIVER) (TELEPHONE MICROPHONE ASSEMBLY POWER SOURCE)

(a) Remove the DCM (Telematics Transceiver) but do not disconnect the connectors.

Click here

*a

Component with harness connected

(DCM (Telematics Transceiver))

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

F134-33 (MCVD) - Body ground

Ignition switch ACC

4 to 6 V

Standard Resistance:

Tester Connection

Condition

Specified Condition

F134-35 (MCI-) - Body ground

Always

Below 1 Ω
OK

REPAIR OR REPLACE HARNESS OR CONNECTOR
NG

5.

REPLACE DCM (TELEMATICS TRANSCEIVER)

(a) Replace the DCM (Telematics Transceiver).

Click here

NOTICE:

  • The ignition switch must be off.
  • Do not swap the DCM (Telematics Transceiver) with one from another vehicle.
NEXT

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