Nissan Leaf. Manual - part 149

AV

U1A05 TCU

AV-587

< DTC/CIRCUIT DIAGNOSIS >

[TELEMATICS SYSTEM]

C

D

E

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U1A05 TCU

DTC Logic

INFOID:0000000010122761

Diagnosis Procedure

INFOID:0000000010122762

Regarding Wiring Diagram information, refer to 

AV-529, "Wiring Diagram"

 (NAVIGATION WITHOUT BOSE) or

AV-549, "Wiring Diagram"

 (NAVIGATION WITH BOSE).

1.

CHECK USB HARNESS CONTINUITY

1. Turn the power switch OFF.

2. Disconnect TCU and AV control unit connectors.

3. Check the continuity between TCU harness connector and AV control unit harness connector.

4. Check the continuity between TCU harness connector and ground.

Is the check result normal?

YES

>> Replace TCU. Refer to 

AV-594, "Removal and Installation"

.

NO

>> Repair or replace the harness or connectors.

DTC

Display contents of CON-

SULT

DTC detection condition

Action to take

U1A05

USB COMM
[U1A05]

It is detected for malfunction of the USB communication 
module (communication disabled) between TCU and AV 
control unit.

• Check the USB harness con-

nection and erase DTC.

• Replace TCU if the malfunction 

constantly occurs.
Refer to 

AV-594, "Removal and 

Installation"

.

TCU

AV control unit

Continuity

Connector

Terminal

Connector

Terminal

M68

47

M97 (without Bose)

M104 (with Bose)

62

Yes

48

61

55

70

56

69

TCU

Ground

Continuity

Connector

Terminal

M68

47

No

48

56

AV-588

< DTC/CIRCUIT DIAGNOSIS >

[TELEMATICS SYSTEM]

U1A07 TEL ANTENNA

U1A07 TEL ANTENNA

DTC Logic

INFOID:0000000010122763

Diagnosis Procedure

INFOID:0000000010122764

Regarding Wiring Diagram information, refer to 

AV-529, "Wiring Diagram"

 (NAVIGATION WITHOUT BOSE) or

AV-549, "Wiring Diagram"

 (NAVIGATION WITH BOSE).

1.

HARNESS INSPECTION

1. Turn the power switch OFF.

2. Disconnect the TEL antenna feeder connector of TCU.

3. Check the continuity between TEL antenna-side harness connector.

Is the check result normal?

YES

>> Replace TCU. Refer to 

AV-594, "Removal and Installation"

.

NO

>> Replace the TEL antenna. Refer to 

AV-597, "Removal and Installation"

.

DTC

Display contents of CON-

SULT

DTC detection condition

Action to take

U1A07

TEL ANTENNA SHORT
[U1A07]

TEL antenna was short-circuited.

• Check the TEL antenna har-

ness connection and the har-
ness condition, and erase 
DTC.

• If poor harness condition or the 

malfunction constantly occurs, 
replace the TEL antenna.
Refer to 

AV-597, "Removal and 

Installation"

.

TEL antenna

Continuity

Connector

Terminal

M113

58

59

No

AV

U1A08 TEL ANTENNA

AV-589

< DTC/CIRCUIT DIAGNOSIS >

[TELEMATICS SYSTEM]

C

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U1A08 TEL ANTENNA

DTC Logic

INFOID:0000000010122765

Diagnosis Procedure

INFOID:0000000010122766

Regarding Wiring Diagram information, refer to 

AV-529, "Wiring Diagram"

 (NAVIGATION WITHOUT BOSE) or

AV-549, "Wiring Diagram"

 (NAVIGATION WITH BOSE).

1.

CHECK OF TEL ANTENNA

1. Turn the power switch OFF.

2. Disconnect the TEL antenna feeder connector.

3. Visually check TEL antenna and antenna feeder.
Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair malfunctioning parts.

2.

CHECK AV CONTROL UNIT VOLTAGE

1. Disconnect TEL antenna connector.

2. Turn power switch ON.

3. Check voltage between TCU and ground.

Is the inspection result normal?

YES

>> Replace TEL antenna. Refer to 

AV-597, "Removal and Installation"

.

NO

>> Replace TCU. Refer to 

AV-594, "Removal and Installation"

.

DTC

Display contents of CON-

SULT

DTC detection condition

Action to take

U1A08

TEL ANTENNA NO CONN
[U1A08]

TEL ANTENNA NO CONN

• Check the harness connec-

tion and erase DTC.

• Replace TCU if the malfunc-

tion constantly occurs. Re-
fer to 

AV-594, "Removal and 

Installation"

.

(+)

(

−)

Reference value

TCU

Terminal

Connector

M113

58

Ground

2.8 V

AV-590

< DTC/CIRCUIT DIAGNOSIS >

[TELEMATICS SYSTEM]

POWER SUPPLY AND GROUND CIRCUIT

POWER SUPPLY AND GROUND CIRCUIT

TCU
TCU : Diagnosis Procedure

INFOID:0000000010122767

Regarding Wiring Diagram information, refer to 

AV-529, "Wiring Diagram"

 (NAVIGATION WITHOUT BOSE) or

AV-549, "Wiring Diagram"

 (NAVIGATION WITH BOSE).

1.

CHECK FUSE

Check if the fuse is blown.

Is the check result normal?

YES

>> GO TO 2.

NO

>> Replace the blown fuse after repairing the affected circuit.

2.

CHECK TCU VOLTAGE CIRCUITS

Check the voltage between the TCU harness connector and ground.

Is the check result normal?

YES

>> GO TO 3.

NO

>> Repair or replace the harness or connectors.

3.

CHECK TCU GROUND CIRCUIT

1. Turn the power switch OFF.

2. Disconnect the TCU connector.

3. Check the continuity between TCU harness connector and ground.

Is the check result normal?

YES

>> Inspection End.

NO

>> Repair or replace the harness or connectors.

Power supply

Fuse No.

BAT

34

Power switch ACC or ON

19

Power switch ON

3

Signal

TCU

Terminal

Test condition

Standard

Reference value

Connector

 (+) 

 (-) 

Power switch

BAT

M67

1

2

OFF

9 – 16 V

Battery Voltage

ACC

3

ACC

9 – 16 V

12 V

ON

4

ON

9 – 16 V

12 V

Signal

Connector

Terminal

Power switch

Continuity

Ground

M67

2

OFF

Yes