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DTC U2145:08 [CONNECTIVITY MASTER UNIT]

id1602a1008700

Without Bose^®

Outline

System malfunction location

Communication error with remote tuner (RT)

Detection condition

•  Connectivity master unit (CMU) detects communication error with remote tuner (RT).

Fail-safe

Not applicable

Possible cause

•  Remote tuner (RT) connector or terminal malfunction

•  Audio amplifier connector or terminal malfunction

•  Connectivity master unit (CMU) connector or terminal malfunction

•  Short to ground or open circuit in remote tuner (RT) power supply circuit

•  Open circuit in remote tuner (RT) ground circuit

•  Short to power supply, short to ground or open circuit in MOST WAKE UP circuit

•  Short to power supply, short to ground or open circuit in MOST communication circuit

•  MOST communication circuit shield wire malfunction

•  Remote tuner (RT) malfunction

•  Connectivity master unit (CMU) malfunction

System malfunction location	Communication error with remote tuner (RT)
Detection condition	• Connectivity master unit (CMU) detects communication error with remote tuner (RT).
Fail-safe	Not applicable
Possible cause	• Remote tuner (RT) connector or terminal malfunction • Audio amplifier connector or terminal malfunction • Connectivity master unit (CMU) connector or terminal malfunction • Short to ground or open circuit in remote tuner (RT) power supply circuit • Open circuit in remote tuner (RT) ground circuit • Short to power supply, short to ground or open circuit in MOST WAKE UP circuit • Short to power supply, short to ground or open circuit in MOST communication circuit • MOST communication circuit shield wire malfunction • Remote tuner (RT) malfunction • Connectivity master unit (CMU) malfunction

Diagnostic Procedure

Step

Inspection

Results

Action

1

VERIFY REMOTE TUNER (RT) OPERATION

•  Output audio in the cabin using the audio amplifier. (Such as radio, navigation)

•  Is audio output from the vehicle speakers?

Yes

Verify that the repairs have been completed.

No

Go to the next step.

2

VERIFY SUPPLY VOLTAGE TO REMOTE TUNER (RT)

•  Measure the voltage at remote tuner (RT) terminal 1A (vehicle wiring harness side).

•  Is the voltage B+?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

3

INSPECT REMOTE TUNER (RT) GROUND CIRCUIT FOR OPEN CIRCUIT

•  Inspect the remote tuner (RT) ground circuit for open circuit.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

4

INSPECT REMOTE TUNER (RT) CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(Refer to the [CONNECTOR INSPECTION] in the workshop manual)

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

5

INSPECT REMOTE TUNER (RT) POWER SUPPLY CIRCUIT FOR SHORT TO GROUND AND OPEN CIRCUIT

•  Inspect the power supply circuit for a short to ground and open circuit.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

6

VERIFY MOST WAKE UP CIRCUIT VOLTAGE

•  Measure the voltage at remote tuner (RT) terminal 1D (vehicle wiring harness side).

•  Is the voltage B+?

Yes

Go to Step 12.

No

Go to the next step.

7

VERIFY OTHER CONNECTIVITY MASTER UNIT (CMU) DTCs

•  Clear the DTC recorded in the memory.
(Refer to the [CLEARING DTC] in the workshop manual)

•  Perform the DTC inspection for the connectivity master unit (CMU).
(Refer to the [DTC INSPECTION] in the workshop manual)

•  Are any of the following DTCs displayed?

―  U0186:02

―  U0186:08

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

(See DTC TABLE [CONNECTIVITY MASTER UNIT (E)].)

No

Go to the next step.

8

INSPECT AUDIO AMPLIFIER CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(Refer to the [CONNECTOR INSPECTION] in the workshop manual)

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

9

INSPECT MOST WAKE UP CIRCUIT FOR SHORT TO GROUND

•  Inspect the applicable circuit for a short to ground.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual))

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

10

INSPECT MOST WAKE UP CIRCUIT FOR SHORT TO POWER SUPPLY

•  Inspect the applicable circuit for a short to power supply.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

11

INSPECT MOST WAKE UP CIRCUIT FOR OPEN CIRCUIT

•  Inspect the applicable circuit for an open circuit.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is the circuit normal?

Yes

Go to Step 13.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

12

INSPECT AUDIO AMPLIFIER CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(Refer to the [CONNECTOR INSPECTION] in the workshop manual)

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

13

INSPECT CONNECTIVITY MASTER UNIT (CMU) CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(Refer to the [CONNECTOR INSPECTION] in the workshop manual)

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

14

INSPECT MOST COMMUNICATION CIRCUIT FOR SHORT TO GROUND

•  Inspect the applicable circuit for a short to ground.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

15

INSPECT MOST COMMUNICATION CIRCUIT FOR SHORT TO POWER SUPPLY

•  Inspect the applicable circuit for a short to power supply.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

16

VERIFY MOST COMMUNICATION CIRCUIT OPEN CIRCUIT

•  Inspect the applicable circuit for an open circuit.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

17

INSPECT FOR CONTINUITY BETWEEN MOST COMMUNICATION CIRCUIT SHIELD WIRE AND GROUND

•  Inspect the applicable circuit for continuity with the body ground.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is there continuity?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

Repair completion verification 1

VERIFY THAT VEHICLE IS REPAIRED

•  Install/connect the part removed/disconnected during the troubleshooting procedure.

•  Clear the DTC recorded in the memory.
(Refer to the [CLEARING DTC] in the workshop manual)

•  Perform the DTC inspection for the connectivity master unit (CMU).
(Refer to the [DTC INSPECTION] in the workshop manual)

•  Is the same Pending DTC present?

Yes

Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.

(Refer to the [CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW] in the workshop manual)

If the CAN communication is normal, perform the diagnosis from Step 1.

•  If the malfunction recurs, replace the connectivity master unit (CMU), then go to the next step.
(Refer to the [CONNECTIVITY MASTER UNIT (CMU) REMOVAL/INSTALLATION] in the workshop manual)

No

Go to the next step.

Repair completion verification 2

VERIFY IF OTHER DTCs ARE DISPLAYED

•  Perform the DTC inspection.
(Refer to the [DTC INSPECTION] in the workshop manual)

•  Are other DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

No

DTC troubleshooting completed.

Step	Inspection	Results	Action
1	VERIFY REMOTE TUNER (RT) OPERATION • Output audio in the cabin using the audio amplifier. (Such as radio, navigation) • Is audio output from the vehicle speakers?	Yes	Verify that the repairs have been completed.
No	Go to the next step.
2	VERIFY SUPPLY VOLTAGE TO REMOTE TUNER (RT) • Measure the voltage at remote tuner (RT) terminal 1A (vehicle wiring harness side). • Is the voltage B+?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
3	INSPECT REMOTE TUNER (RT) GROUND CIRCUIT FOR OPEN CIRCUIT • Inspect the remote tuner (RT) ground circuit for open circuit. (Refer to the [CIRCUIT INSPECTION] in the workshop manual) • Is the circuit normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
4	INSPECT REMOTE TUNER (RT) CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (Refer to the [CONNECTOR INSPECTION] in the workshop manual) • Are the connector and terminal normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT REMOTE TUNER (RT) POWER SUPPLY CIRCUIT FOR SHORT TO GROUND AND OPEN CIRCUIT • Inspect the power supply circuit for a short to ground and open circuit. (Refer to the [CIRCUIT INSPECTION] in the workshop manual) • Is the circuit normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
6	VERIFY MOST WAKE UP CIRCUIT VOLTAGE • Measure the voltage at remote tuner (RT) terminal 1D (vehicle wiring harness side). • Is the voltage B+?	Yes	Go to Step 12.
No	Go to the next step.
7	VERIFY OTHER CONNECTIVITY MASTER UNIT (CMU) DTCs • Clear the DTC recorded in the memory. (Refer to the [CLEARING DTC] in the workshop manual) • Perform the DTC inspection for the connectivity master unit (CMU). (Refer to the [DTC INSPECTION] in the workshop manual) • Are any of the following DTCs displayed? ― U0186:02 ― U0186:08	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [CONNECTIVITY MASTER UNIT (E)].)
No	Go to the next step.
8	INSPECT AUDIO AMPLIFIER CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (Refer to the [CONNECTOR INSPECTION] in the workshop manual) • Are the connector and terminal normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
9	INSPECT MOST WAKE UP CIRCUIT FOR SHORT TO GROUND • Inspect the applicable circuit for a short to ground. (Refer to the [CIRCUIT INSPECTION] in the workshop manual)) • Is the circuit normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
10	INSPECT MOST WAKE UP CIRCUIT FOR SHORT TO POWER SUPPLY • Inspect the applicable circuit for a short to power supply. (Refer to the [CIRCUIT INSPECTION] in the workshop manual) • Is the circuit normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
11	INSPECT MOST WAKE UP CIRCUIT FOR OPEN CIRCUIT • Inspect the applicable circuit for an open circuit. (Refer to the [CIRCUIT INSPECTION] in the workshop manual) • Is the circuit normal?	Yes	Go to Step 13.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
12	INSPECT AUDIO AMPLIFIER CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (Refer to the [CONNECTOR INSPECTION] in the workshop manual) • Are the connector and terminal normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
13	INSPECT CONNECTIVITY MASTER UNIT (CMU) CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (Refer to the [CONNECTOR INSPECTION] in the workshop manual) • Are the connector and terminal normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
14	INSPECT MOST COMMUNICATION CIRCUIT FOR SHORT TO GROUND • Inspect the applicable circuit for a short to ground. (Refer to the [CIRCUIT INSPECTION] in the workshop manual) • Is the circuit normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
15	INSPECT MOST COMMUNICATION CIRCUIT FOR SHORT TO POWER SUPPLY • Inspect the applicable circuit for a short to power supply. (Refer to the [CIRCUIT INSPECTION] in the workshop manual) • Is the circuit normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
16	VERIFY MOST COMMUNICATION CIRCUIT OPEN CIRCUIT • Inspect the applicable circuit for an open circuit. (Refer to the [CIRCUIT INSPECTION] in the workshop manual) • Is the circuit normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
17	INSPECT FOR CONTINUITY BETWEEN MOST COMMUNICATION CIRCUIT SHIELD WIRE AND GROUND • Inspect the applicable circuit for continuity with the body ground. (Refer to the [CIRCUIT INSPECTION] in the workshop manual) • Is there continuity?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
Repair completion verification 1	VERIFY THAT VEHICLE IS REPAIRED • Install/connect the part removed/disconnected during the troubleshooting procedure. • Clear the DTC recorded in the memory. (Refer to the [CLEARING DTC] in the workshop manual) • Perform the DTC inspection for the connectivity master unit (CMU). (Refer to the [DTC INSPECTION] in the workshop manual) • Is the same Pending DTC present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (Refer to the [CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW] in the workshop manual) If the CAN communication is normal, perform the diagnosis from Step 1. • If the malfunction recurs, replace the connectivity master unit (CMU), then go to the next step. (Refer to the [CONNECTIVITY MASTER UNIT (CMU) REMOVAL/INSTALLATION] in the workshop manual)
No	Go to the next step.
Repair completion verification 2	VERIFY IF OTHER DTCs ARE DISPLAYED • Perform the DTC inspection. (Refer to the [DTC INSPECTION] in the workshop manual) • Are other DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
No	DTC troubleshooting completed.

With Bose^®

Outline

System malfunction location	Communication error with remote tuner (RT)
Detection condition	• Connectivity master unit (CMU) detects communication error with remote tuner (RT).
Fail-safe	Not applicable
Possible cause	• Remote tuner (RT) connector or terminal malfunction • Audio amplifier connector or terminal malfunction • Connectivity master unit (CMU) connector or terminal malfunction • Short to ground or open circuit in remote tuner (RT) power supply circuit • Open circuit in remote tuner (RT) ground circuit • Short to power supply, short to ground or open circuit in MOST WAKE UP circuit • Short to power supply, short to ground or open circuit in MOST communication circuit • MOST communication circuit shield wire malfunction • Remote tuner (RT) malfunction • Connectivity master unit (CMU) malfunction

Diagnostic Procedure

Step

Inspection

Results

Action

1

VERIFY REMOTE TUNER (RT) OPERATION

•  Output audio in the cabin using the audio amplifier. (Such as radio, navigation)

•  Is audio output from the vehicle speakers?

Yes

Verify that the repairs have been completed.

No

Go to the next step.

2

VERIFY SUPPLY VOLTAGE TO REMOTE TUNER (RT)

•  Measure the voltage at remote tuner (RT) terminal 1A (vehicle wiring harness side).

•  Is the voltage B+?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

3

INSPECT REMOTE TUNER (RT) GROUND CIRCUIT FOR OPEN CIRCUIT

•  Inspect the remote tuner (RT) ground circuit for open circuit.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

4

INSPECT REMOTE TUNER (RT) CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(Refer to the [CONNECTOR INSPECTION] in the workshop manual)

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

5

INSPECT REMOTE TUNER (RT) POWER SUPPLY CIRCUIT FOR SHORT TO GROUND AND OPEN CIRCUIT

•  Inspect the power supply circuit for a short to ground and open circuit.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

6

VERIFY MOST WAKE UP CIRCUIT VOLTAGE

•  Measure the voltage at remote tuner (RT) terminal 1D (vehicle wiring harness side).

•  Is the voltage B+?

Yes

Go to Step 12.

No

Go to the next step.

7

VERIFY OTHER CONNECTIVITY MASTER UNIT (CMU) DTCs

•  Clear the DTC recorded in the memory.
(Refer to the [CLEARING DTC] in the workshop manual)

•  Perform the DTC inspection for the connectivity master unit (CMU).
(Refer to the [DTC INSPECTION] in the workshop manual)

•  Are any of the following DTCs displayed?

―  U0186:02

―  U0186:08

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

(See DTC TABLE [CONNECTIVITY MASTER UNIT (E)].)

No

Go to the next step.

8

INSPECT AUDIO AMPLIFIER CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(Refer to the [CONNECTOR INSPECTION] in the workshop manual)

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

9

INSPECT MOST WAKE UP CIRCUIT FOR SHORT TO GROUND

•  Inspect the applicable circuit for a short to ground.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

10

INSPECT MOST WAKE UP CIRCUIT FOR SHORT TO POWER SUPPLY

•  Inspect the applicable circuit for a short to power supply.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

11

VERIFY MOST WAKE UP CIRCUIT OPEN CIRCUIT

•  Inspect the applicable circuit for an open circuit.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is the circuit normal?

Yes

Go to Step 13.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

12

INSPECT AUDIO AMPLIFIER CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(Refer to the [CONNECTOR INSPECTION] in the workshop manual)

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

13

INSPECT CONNECTIVITY MASTER UNIT (CMU) CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(Refer to the [CONNECTOR INSPECTION] in the workshop manual)

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

14

INSPECT MOST COMMUNICATION CIRCUIT FOR SHORT TO GROUND

•  Inspect the applicable circuit for a short to ground.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

15

INSPECT MOST COMMUNICATION CIRCUIT FOR SHORT TO POWER SUPPLY

•  Inspect the applicable circuit for a short to power supply.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

16

VERIFY MOST COMMUNICATION CIRCUIT OPEN CIRCUIT

•  Inspect the applicable circuit for an open circuit.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

17

INSPECT FOR CONTINUITY BETWEEN MOST COMMUNICATION CIRCUIT SHIELD WIRE AND GROUND

•  Inspect the applicable circuit for continuity with the body ground.
(Refer to the [CIRCUIT INSPECTION] in the workshop manual)

•  Is there continuity?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

Repair completion verification 1

VERIFY THAT VEHICLE IS REPAIRED

•  Install/connect the part removed/disconnected during the troubleshooting procedure.

•  Clear the DTC recorded in the memory.
(Refer to the [CLEARING DTC] in the workshop manual)

•  Perform the DTC inspection for the connectivity master unit (CMU).
(Refer to the [DTC INSPECTION] in the workshop manual)

•  Is the same Pending DTC present?

Yes

Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.

(Refer to the [CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW] in the workshop manual)

If the CAN communication is normal, perform the diagnosis from Step 1.

•  If the malfunction recurs, replace the connectivity master unit (CMU), then go to the next step.
(Refer to the [CONNECTIVITY MASTER UNIT (CMU) REMOVAL/INSTALLATION] in the workshop manual)

No

Go to the next step.

Repair completion verification 2

VERIFY IF OTHER DTCs ARE DISPLAYED

•  Perform the DTC inspection.
(Refer to the [DTC INSPECTION] in the workshop manual)

•  Are other DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

No

DTC troubleshooting completed.