Nissan Pathfinder: Dtc/circuit Diagnosis (B24a6-15 in-Vehicle Sensor ... U2140-87 Can Comm Err (ecm))

• B24a6-15 in-Vehicle Sensor
• B24b4-02 A/c Control Comm
• B24c6-12 Blower Motor Control
• B24f5-93 Mode Door Motor
• U1ca1-08 A/c Switch Assembly Communication
• U1ca2-08 Door Motor Communication
• U1caa-02 Mode Door Motor
• U2140-87 Can Comm Err (ecm)

B24a6-15 in-Vehicle Sensor Nissan Pathfinder 2022

DTC Description

DTC DETECTION LOGIC

DTC No.	CONSULT screen terms (Trouble diagnosis content)	DTC detection condition
B24A6-15	IN-Nissan Pathfinder Vehicle SENSOR (In-vehicle sensor)	Diagnosis condition	Ignition switch ON
		Signal (Terminal)	In-Nissan Pathfinder vehicle sensor signal
		Threshold	The in-Nissan Pathfinder vehicle sensor recognition temperature is too low [less than -44°F (-42°C)]
		Diagnosis delay time	2 second or more

POSSIBLE CAUSE

• Front in-vehicle sensor

• A/C auto amp.

• Harness or connectors (the sensor circuit is open or shorted to battery)

FAIL-SAFE

In-vehicle temperature is calculated as 77°F (25°C) and air conditioning system is controlled.

DTC CONFIRMATION PROCEDURE

PERFORM DTC CONFIRMATION PROCEDURE

CONSULT

1. Ignition switch ON.

2. Select “Self Diagnostic Result” mode of “HVAC”.

3. Check DTC.

Is DTC detected?

YES>>

Refer to DTC Diagnosis Procedure.

NO>>

To check malfunction symptom before repair: Refer to Intermittent Incident.

NO>>

Confirmation after repair: Inspection End.

DTC Diagnosis Procedure

CHECK FRONT IN-VEHICLE SENSOR SIGNAL

1. Ignition switch ON.

2. Check voltage between A/C auto amp. harness connector.

   A/C auto amp.			Voltage (Approx.)
   Connector	Terminals
   	+	-
   M60	48	78

Is the inspection result normal?

YES>>

Replace A/C auto amp. Refer to Removal and Installation.

NO>>

GO TO 2.

CHECK FRONT IN-Nissan Pathfinder Vehicle SENSOR POWER SUPPLY

1. Ignition switch OFF.

2. Disconnect front in-vehicle sensor connector.

3. Ignition switch ON.

4. Check voltage between front in-Nissan Pathfinder vehicle sensor harness connector and ground.

   +		-	Voltage (Approx.)
   Front in-Nissan Pathfinder vehicle sensor
   Connector	Terminal
   M102	1	Ground	5 V

Is the inspection result normal?

YES>>

GO TO 3.

NO>>

GO TO 5.

CHECK FRONT IN-Nissan Pathfinder Vehicle SENSOR GROUND CIRCUIT FOR OPEN

1. Ignition switch OFF.

2. Disconnect A/C auto amp. connector.

3. Check continuity between front in-Nissan Pathfinder vehicle sensor harness connector and A/C auto amp. harness connector.

   Front in-Nissan Pathfinder vehicle sensor		A/C auto amp.		Continuity
   Connector	Terminal	Connector	Terminal
   M102	2	M60	78	Yes

Is the inspection result normal?

YES>>

GO TO 4.

NO>>

Repair harness or connector.

CHECK FRONT IN-Nissan Pathfinder Vehicle SENSOR

Check front in-vehicle sensor. Refer to Component Inspection.

Is the inspection result normal?

YES>>

Replace A/C auto amp. Refer to Removal and Installation.

NO>>

Replace front in-Nissan Pathfinder vehicle sensor. Refer to Removal and Installation.

CHECK FRONT IN-Nissan Pathfinder Vehicle SENSOR POWER SUPPLY CIRCUIT FOR OPEN

1. Ignition switch OFF.

2. Disconnect A/C auto amp. connector.

3. Check continuity between front in-Nissan Pathfinder vehicle sensor harness connector and A/C auto amp. harness connector.

   Front in-Nissan Pathfinder vehicle sensor		A/C auto amp.		Continuity
   Connector	Terminal	Connector	Terminal
   M102	1	M60	48	Yes

Is the inspection result normal?

YES>>

GO TO 6.

NO>>

Repair harness or connector.

CHECK FRONT IN-Nissan Pathfinder Vehicle SENSOR POWER SUPPLY CIRCUIT FOR SHORT

Check voltage between front in-vehicle sensor harness connector and ground.

+		-	Voltage (Approx.)
Front in-Nissan Pathfinder vehicle sensor
Connector	Terminal
M102	1	Ground	0 V

Is the inspection result normal?

YES>>

Replace A/C auto amp. Refer to Removal and Installation.

NO>>

Repair harness or connector.

Component Inspection

CHECK FRONT IN-VEHICLE SENSOR

1. Ignition switch OFF.

2. Remove front in-Nissan Pathfinder vehicle sensor. Refer to Removal and Installation.

3. Check resistance between front in-vehicle sensor terminals. Refer to applicable table for the normal value.

   Front in-Nissan Pathfinder vehicle sensor		Condition	Resistance: kΩ
   Terminals		Temperature: °F (°C)
   1	2	−4 (−20)	16.50
   		14 (−10)	9.92
   		32 (0)	6.19
   		50 (10)	3.99
   		68 (20)	2.65
   		77 (25)	2.19
   		86 (30)	1.81
   		104 (40)	1.27

Is the inspection result normal?

YES>>

Inspection End.

NO>>

Replace front in-Nissan Pathfinder vehicle sensor. Refer to Removal and Installation.

B24b4-02 A/c Control Comm Nissan Pathfinder 2025

DTC Description

DTC DETECTION LOGIC

DTC No.	CONSULT screen terms (Trouble diagnosis content)	DTC detection condition
B24B4-02	A/C CONTROL COMM (Air conditioning control communication)	Diagnosis condition	Ignition switch ON
		Signal (Terminal)	LIN (A/C switch assembly) signal
		Threshold	Receive internal circuit error message via front A/C switch assembly to LIN communication
		Diagnosis delay time	30 second or more

POSSIBLE CAUSE

Front A/C switch assembly (internal circuit malfunction)

FAIL-SAFE

—

DTC CONFIRMATION PROCEDURE

PERFORM SELF-DIAGNOSIS

CONSULT

1. Ignition switch ON.

2. Select “Self Diagnostic Result” mode of “HVAC”.

3. Check DTC.

Is DTC detected?

YES>>

Refer to DTC Diagnosis Procedure.

NO>>

To check malfunction symptom before repair: Refer to Intermittent Incident.

NO>>

Confirmation after repair: Inspection End.

DTC Diagnosis Procedure

PERFORM SELF DIAGNOSTIC RESULT

CONSULT

1. Ignition switch ON.

2. Select “Self Diagnostic Result” mode of “HVAC”.

3. Select “ERASE”.

4. Ignition switch OFF.

5. Ignition switch ON.

6. Perform “DTC CONFIRMATION PROCEDURE”. Refer to DTC Description.

Is DTC detected again?

YES>>

Replace front A/C switch assembly. Refer to Removal and Installation.

NO>>

Inspection End.

B24c6-12 Blower Motor Control Nissan Pathfinder 2022

DTC Description

DTC DETECTION LOGIC

DTC No.	CONSULT screen terms (Trouble diagnosis content)		DTC detection condition
B24C6-12	BLOWER MOTOR CONTROL (Blower motor control)	[CIRCUIT SHORT TO GROUND]	Diagnosis condition	When ignition switch is ON
			Signal (Terminal)	Blower motor control signal
			Threshold	Blower motor control signal circuit has a short to ground
			Diagnosis delay time	—

POSSIBLE CAUSE

• Harness or connectors (blower motor control signal circuit is shorted to ground)

• A/C auto amp.

FAIL-SAFE

—

DTC CONFIRMATION PROCEDURE

PERFORM SELF DIAGNOSTIC RESULT

CONSULT

1. Ignition switch ON.

2. Select “Self Diagnostic Result” mode of “HVAC”.

3. Check DTC.

Is DTC detected?

YES>>

Refer to DTC Diagnosis Procedure.

NO>>

To check malfunction symptom before repair: Refer to Intermittent Incident.

NO>>

Confirmation after repair: Inspection End.

DTC Diagnosis Procedure

CHECK FRONT BLOWER MOTOR CONTROL SIGNAL

1. Ignition switch ON.

2. Check duty ratios between front blower motor harness connector and ground by using an oscilloscope.

   (+)		(–)	Condition	Output waveform (Approx.)
   Front blower motor
   Connector	Terminal
   M187	2	Ground	Front blower motor: OFF	Battery voltage
   			Front blower motor: 1st speed (manual)
   			Front blower motor: 7th speed (manual)

Is the inspection result normal?

YES>>

Replace front blower motor. Refer to Removal and Installation.

NO>>

GO TO 2.

CHECK FRONT BLOWER MOTOR CONTROL SIGNAL CIRCUIT FOR OPEN

1. Ignition switch OFF.

2. Disconnect front blower motor connector and A/C auto amp. connector.

3. Check continuity between front blower motor harness connector and A/C auto amp. harness connector.

   Front blower motor		A/C auto amp.		Continuity
   Connector	Terminal	Connector	Terminal
   M187	2	M50	34	Yes

4. Check continuity between front blower motor harness connector and ground.

   Front blower motor		(–)	Continuity
   Connector	Terminal
   M187	2	Ground	No

Is the inspection result normal?

YES>>

Replace the A/C auto amp. Refer to Removal and Installation.

NO>>

Repair the harnesses or connectors.

B24f5-93 Mode Door Motor Nissan Pathfinder SUV

DTC Description

DTC DETECTION LOGIC

NOTE:

If all of door motors DTC (B2480-93, B24F5-93, B24F6-93, B24F7-93, B24F8-93) are detected, check “DOOR MOTOR CIRCUIT”. Refer to Diagnosis Procedure.

DTC No.	CONSULT screen terms (Trouble diagnosis content)	DTC detection condition
B24F5-93	Mode door motor (Mode door motor)	Diagnosis condition	Ignition switch ON
		Signal (Terminal)	LIN (door motor) signal
		Threshold	Drive error of mode door motor (front) is detected
		Diagnosis delay time	2 second or more

POSSIBLE CAUSE

• Harness and connector [mode door motor (front) circuit is open or shorted to ground]

• Mode door motor (front) installation condition

• Mode door motor (front)

• A/C auto amp.

FAIL-SAFE

—

DTC CONFIRMATION PROCEDURE

PERFORM DTC CONFIRMATION PROCEDURE

CONSULT

1. Start the engine.

2. Select “Self Diagnostic Result” mode of “HVAC”.

3. Check DTC.

Is DTC detected?

YES>>

Refer to DTC Diagnosis Procedure.

NO>>

To check malfunction symptom before repair: Refer to Intermittent Incident.

NO>>

Confirmation after repair: Inspection End.

DTC Diagnosis Procedure

CHECK MODE DOOR MOTOR (FRONT) POWER SUPPLY

1. Ignition switch ON.

2. Check voltage between mode door motor (front) harness connector and ground.

+		−	Voltage (Approx.)
Mode door motor (front)
Connector	Terminal
M129	1	Ground	Battery voltage

Is the inspection result normal?

YES>>

GO TO 2.

NO>>

GO TO 5.

CHECK MODE DOOR MOTOR (FRONT) GROUND CIRCUIT FOR OPEN

1. Ignition switch OFF.

2. Disconnect mode door motor (front) connector and A/C auto amp. connector.

3. Check continuity between mode door motor (front) harness connector and A/C auto amp. harness connector.

   Mode door motor (front)		A/C auto amp.		Continuity
   Connector	Terminal	Connector	Terminal
   M129	2	M50	27	Yes

Is the inspection result normal?

YES>>

GO TO 3.

NO>>

Repair harness or connector.

CHECK MODE DOOR MOTOR (FRONT) LIN SIGNAL CIRCUIT

1. Connect mode door motor (front) connector and A/C auto amp. connector.

2. Ignition switch ON.

3. Confirm output waveform between mode door motor (front) harness connector and ground with oscilloscope.

   +		−	Output waveform
   Mode door motor
   Connector	Terminal
   M129	3	Ground

Is the inspection result normal?

YES>>

GO TO 4.

NO>>

GO TO 6.

CHECK INSTALLATION OF MODE DOOR MOTOR (FRONT)

Check mode door motor (front) is properly installed. Refer to Exploded View.

Is the inspection result normal?

YES>>

Replace mode door motor (front). Refer to Removal and Installation - Mode Door Motor (Front).

NO>>

Repair or replace malfunctioning part.

CHECK MODE DOOR MOTOR (FRONT) POWER SUPPLY CIRCUIT FOR OPEN

1. Ignition switch OFF.

2. Disconnect mode door motor (front) connector and A/C auto amp. connector.

3. Check continuity between mode door motor (front) harness connector and A/C auto amp. harness connector.

   Mode door motor (front)		A/C auto amp.		Continuity
   Connector	Terminal	Connector	Terminal
   M129	1	M50	1	Yes

Is the inspection result normal?

YES>>

Replace A/C auto amp. Refer to Removal and Installation.

NO>>

Repair harness or connector.

CHECK MODE DOOR MOTOR (FRONT) LIN SIGNAL CIRCUIT FOR OPEN

1. Ignition switch OFF.

2. Disconnect mode door motor (front) connector and A/C auto amp. connector.

3. Check continuity between mode door motor (front) harness connector and A/C auto amp. harness connector.

   Mode door motor (front)		A/C auto amp.		Continuity
   Connector	Terminal	Connector	Terminal
   M129	3	M50	2	Yes

Is the inspection result normal?

YES>>

Replace A/C auto amp. Refer to Removal and Installation.

NO>>

Repair harness or connector.

U1ca1-08 A/c Switch Assembly Communication Nissan Pathfinder 2025

DTC Description

DTC DETECTION LOGIC

DTC No.	CONSULT screen terms (Trouble diagnosis content)	DTC detection condition
U1CA1-08	LIN communication 2 (Local interconnect network communication 2)	Diagnosis condition	Ignition switch ON
		Signal (Terminal)	LIN (A/C control) signal
		Threshold	A/C auto amp. is not transmitting or receiving LIN communication with front A/C switch assembly or rear A/C switch assembly
		Diagnosis delay time	2 second or more

POSSIBLE CAUSE

• Front A/C switch assembly

• Rear A/C switch assembly

• A/C auto amp.

FAIL-SAFE

—

DTC CONFIRMATION PROCEDURE

PERFORM DTC CONFIRMATION PROCEDURE

CONSULT

1. Ignition switch ON.

2. Select “Self Diagnostic Result” mode of “HVAC”.

3. Check DTC.

Is DTC detected?

YES>>

Refer to DTC Diagnosis Procedure.

NO>>

To check malfunction symptom before repair: Refer to Intermittent Incident.

NO>>

Confirmation after repair: Inspection End.

DTC Diagnosis Procedure

CHECK DTC

CONSULT

1. Ignition switch ON.

2. Select “Self Diagnostic Result” mode of “HVAC”.

3. Check following DTC:

   DTC	Items (CONSULT screen terms)	Reference
   B24B4-02	A/C CONTROL COMM	DTC Description
   U1CB1-02	A/C control 2 communication	DTC Description

Is DTC detected?

YES>>

Perform DTC diagnosis procedure that is detecting.

NO>>

Replace A/C auto amp. Refer to Removal and Installation.

U1ca2-08 Door Motor Communication Nissan Pathfinder Fifth generation

DTC Description

DTC DETECTION LOGIC

DTC No.	CONSULT screen terms (Trouble diagnosis content)	DTC detection condition
U1CA2-08	LIN communication 3 (Local interconnect network communication 3)	Diagnosis condition	Ignition switch ON
		Signal (Terminal)	LIN (door motor) signal
		Threshold	A/C auto amp. is not transmitting or receiving LIN communication with each door motor
		Diagnosis delay time	2 second or more

POSSIBLE CAUSE

• Harness and connector (door motor circuit is open or shorted to ground)

• Each door motor

• A/C auto amp.

FAIL-SAFE

—

DTC CONFIRMATION PROCEDURE

PERFORM DTC CONFIRMATION PROCEDURE

CONSULT

1. Start the engine.

2. Select “Self Diagnostic Result” mode of “HVAC”.

3. Check DTC.

Is DTC detected?

YES>>

Refer to DTC Diagnosis Procedure.

NO>>

To check malfunction symptom before repair: Refer to Intermittent Incident.

NO>>

Confirmation after repair: Inspection End.

DTC Diagnosis Procedure

CHECK DTC

CONSULT

1. Start the engine.

2. Select “Self Diagnostic Result” mode of “HVAC”.

3. Check following DTC:

   DTC	Items (CONSULT screen terms)	Reference
   U1CAA-02	Mode door motor	DTC Description
   U1CAB-02	Intake door motor	DTC Description
   U1CAC-02	Air mix door motor 1	DTC Description
   U1CAD-02	Air mix door motor 2	DTC Description
   U1CAE-02	Rear air mix door motor	DTC Description

Is DTC detected?

YES>>

Perform DTC diagnosis procedure that is detecting.

NO>>

Replace A/C auto amp. Refer to Removal and Installation.

U1caa-02 Mode Door Motor Nissan Pathfinder 5th Gen

DTC Description

DTC DETECTION LOGIC

DTC No.	CONSULT screen terms (Trouble diagnosis content)	DTC detection condition
U1CAA-02	Mode door motor (Mode door motor)	Diagnosis condition	Ignition switch ON
		Signal (Terminal)	LIN (door motor) signal
		Threshold	A/C auto amp. is not transmitting or receiving LIN communication with mode door motor (front)
		Diagnosis delay time	2 second or more

POSSIBLE CAUSE

• Harness and connector [mode door motor (front) circuit is open or shorted to ground]

• Mode door motor (front)

• A/C auto amp.

FAIL-SAFE

—

DTC CONFIRMATION PROCEDURE

PERFORM DTC CONFIRMATION PROCEDURE

CONSULT

1. Start the engine.

2. Select “Self Diagnostic Result” mode of “HVAC”.

3. Check DTC.

Is DTC detected?

YES>>

Refer to DTC Diagnosis Procedure.

NO>>

To check malfunction symptom before repair: Refer to Intermittent Incident.

NO>>

Confirmation after repair: Inspection End.

DTC Diagnosis Procedure

CHECK MODE DOOR MOTOR (FRONT) POWER SUPPLY

1. Ignition switch ON.

2. Check voltage between mode door motor (front) harness connector and ground.

+		−	Voltage (Approx.)
Mode door motor (front)
Connector	Terminal
M129	1	Ground	Battery voltage

Is the inspection result normal?

YES>>

GO TO 2.

NO>>

GO TO 4.

CHECK MODE DOOR MOTOR (FRONT) GROUND CIRCUIT FOR OPEN

1. Ignition switch OFF.

2. Disconnect mode door motor (front) connector and A/C auto amp. connector.

3. Check continuity between mode door motor (front) harness connector and A/C auto amp. harness connector.

   Mode door motor (front)		A/C auto amp.		Continuity
   Connector	Terminal	Connector	Terminal
   M129	2	M50	27	Yes

Is the inspection result normal?

YES>>

GO TO 3.

NO>>

Repair harness or connector.

CHECK MODE DOOR MOTOR (FRONT) LIN SIGNAL CIRCUIT

1. Connect mode door motor (front) connector and A/C auto amp. connector.

2. Ignition switch ON.

3. Confirm output waveform between mode door motor (front) harness connector and ground with oscilloscope.

   +		−	Output waveform
   Mode door motor (front)
   Connector	Terminal
   M129	3	Ground

Is the inspection result normal?

YES>>

Replace mode door motor (front). Refer to Removal and Installation - Mode Door Motor (Front).

NO>>

GO TO 6.

CHECK MODE DOOR MOTOR (FRONT) POWER SUPPLY CIRCUIT FOR OPEN

1. Ignition switch OFF.

2. Disconnect mode door motor (front) connector and A/C auto amp. connector.

3. Check continuity between mode door motor (front) harness connector and A/C auto amp. harness connector.

   Mode door motor (front)		A/C auto amp.		Continuity
   Connector	Terminal	Connector	Terminal
   M129	1	M50	1	Yes

Is the inspection result normal?

YES>>

GO TO 5.

NO>>

Repair harness or connector.

CHECK MODE DOOR MOTOR (FRONT) POWER SUPPLY CIRCUIT FOR SHORT

1. Disconnect following connectors:

   • Air mix door motor LH

   • Air mix door motor RH

   • Air mix door motor (rear)

   • Intake door motor

   • Mode door motor (rear)

2. Check continuity between mode door motor harness connector and ground.

   Mode door motor (front)		—	Continuity
   Connector	Terminal
   M129	1	Ground	No

Is the inspection result normal?

YES>>

Replace A/C auto amp. Refer to Removal and Installation.

NO>>

Repair harness or connector.

CHECK MODE DOOR MOTOR (FRONT) LIN SIGNAL CIRCUIT FOR OPEN

1. Ignition switch OFF.

2. Disconnect mode door motor (front) connector and A/C auto amp. connector.

3. Check continuity between mode door motor (front) harness connector and A/C auto amp. harness connector.

   Mode door motor (front)		A/C auto amp.		Continuity
   Connector	Terminal	Connector	Terminal
   M129	3	M50	2	Yes

Is the inspection result normal?

YES>>

GO TO 7.

NO>>

Repair harness or connector.

CHECK MODE DOOR MOTOR (FRONT) LIN SIGNAL CIRCUIT FOR SHORT

1. Disconnect following connectors:

   • Air mix door motor LH

   • Air mix door motor RH

   • Air mix door motor (rear)

   • Intake door motor

   • Mode door motor (rear)

2. Check continuity between mode door motor (front) harness connector and ground.

   Mode door motor (front)		—	Continuity
   Connector	Terminal
   M129	3	Ground	No

Is the inspection result normal?

YES>>

Replace A/C auto amp. Refer to Removal and Installation.

NO>>

Repair harness or connector.

U2140-87 Can Comm Err (ecm) Nissan Pathfinder 2022

DTC Description

DESCRIPTION

CAN (Controller Area Network) is a serial communication line for real time applications. It is an on-Nissan Pathfinder vehicle multiplex communication line with high data communication speed and excellent error detection ability. Modern Nissan Pathfinder vehicle is equipped with many electronic control unit, and each control unit shares information and links with other control units during operation (not independent). In CAN communication, control units are connected with 2 communication lines (CAN-High line, CAN-Low line) allowing a high rate of information transmission with less wiring. Each control unit transmits/receives data but selectively reads required data only. CAN Communication Signal Chart. Refer to CAN Communication Signal Chart.

DTC DETECTION LOGIC

DTC No.	CONSULT screen items (Trouble diagnosis content)	DTC Detection Condition
U2140–87	CAN comm err (ECM) [CAN communication error (ECM)]	Diagnosis condition	Ignition switch ON
		Signal (terminal)	CAN communication signal
		Threshold	A/C auto amp. is not transmitting or receiving CAN communication signal
		Diagnosis delay time	2 seconds or more

POSSIBLE CAUSE

CAN communication system

FAIL-SAFE

—

DTC CONFIRMATION PROCEDURE

PERFORM SELF-DIAGNOSIS

CONSULT

1. Ignition switch ON.

2. Select “Self Diagnostic Result” mode of “HVAC”.

3. Check DTC.

Is DTC detected?

YES>>

Refer to DTC Diagnosis Procedure.

NO>>

To check malfunction symptom before repair: Refer to Intermittent Incident.

NO>>

Confirmation after repair: Inspection End.

DTC Diagnosis Procedure

CHECK CAN COMMUNICATION SYSTEM

Check CAN communication system. Refer to Trouble Diagnosis Flow Chart.

>>

Inspection End.