Nissan Sentra B18 (2020-2025) Service Manual: Turn Signal Lamp Circuit

Component Function Check

1. CHECK TURN SIGNAL LAMP OPERATION

   1. CONSULT

      1. Select “FLASHER” in "Active Test" mode of “BCM(FLASHER)".

      2. With operating the test item, check that the turn signal lamp is blinks.

         RH	: Turn signal lamp RH blink
         LH	: Turn signal lamp LH blink
         LH/RH	: Turn signal lamps LH and RH blink

   Is the inspection result normal?

   YES >>

   Turn signal lamp circuit is normal.

   NO >>

   Refer to Diagnosis Procedure.

Diagnosis Procedure

1. CHECK TURN SIGNAL LAMP BULB

   1. Check the turn signal lamp bulb. Refer to Component Inspection.

   Is the inspection result normal?

   YES >>

   GO TO 2.

   NO >>

   Front turn signal lamp: Replace corresponding front combination lamp bulb. Refer to Bulb Replacement.

   NO >>

   Rear turn signal lamp: Replace corresponding rear combination lamp (body side) bulb. Refer to Bulb Replacement.

   NO >>

   Side turn signal lamp: Replace corresponding door mirror turn signal lamp. Refer to Removal and Installation.

2. CHECK SYMPTOM

   1. Check symptom (A or B).

      Symptom
      A	All of turn signal lamp do not blink
      B	Applicable side performs high flasher activation

   Which symptom is detected?

   A>>

   GO TO 3.

   B>>

   GO TO 5.

3. CHECK FUSE

   1. 1. Ignition switch OFF.

      2. Check if the following BCM fuses are blown:

         Component	Location	Fuse No.	Capacity
         BCM	Fuse block (J/B)	41	5 A
         		32	10 A

   Is the fuse blown (open)?

   YES >>

   Replace the blown fuse after repairing the affected circuit.

   NO >>

   GO TO 4.

4. CHECK BCM POWER SUPPLY (TURN SIGNAL LAMP)

   1. 1. Disconnect BCM connector.

      2. Check voltage between BCM harness connector and ground.

         +		-	Voltage (Approx.)
         BCM
         Connector	Terminal
         M84	7	Ground	Battery voltage
         M20	133

   Is the inspection result normal?

   YES >>

   Replace BCM. Refer to Removal and Installation.

   NO >>

   Repair or replace harness.

5. CHECK TURN SIGNAL LAMP OUTPUT VOLTAGE

   1. 1. Ignition switch OFF.

      2. Disconnect the following connectors:

         • Front combination lamp LH

         • Front combination lamp RH

         • Door mirror LH

         • Door mirror RH

         • Rear combination lamp LH (body side)

         • Rear combination lamp RH (body side)

      3. Ignition switch ON.

      4. With operating the turn signal switch, check voltage between BCM harness connector and ground.

         Front turn signal lamp

         +			-	Condition		Voltage (Approx.)
         BCM
         Connector		Terminal
         RH	M142	116	Ground	Turn signal switch	Right	Blinking : Battery voltage
         					Center	0V
         LH		128			Left	Blinking : Battery voltage
         					Center	0V

         Side turn signal lamp

         +			-	Condition		Voltage (Approx.)
         BCM
         Connector		Terminal
         RH	M84	1	Ground	Turn signal switch	Right	Blinking : Battery voltage
         					Center	0V
         LH		21			Left	Blinking : Battery voltage
         					Center	0V

         Rear turn signal lamp

         +			-	Condition		Voltage (Approx.)
         BCM
         Connector		Terminal
         RH	M21	159	Ground	Turn signal switch	Right	Blinking : Battery voltage
         					Center	0V
         LH		151			Left	Blinking : Battery voltage
         					Center	0V

   Is the inspection result normal?

   YES >>

   GO TO 7.

   NO >>

   GO TO 6.

6. CHECK TURN SIGNAL LAMP POWER SUPPLY CIRCUIT (SHORT)

   1. 1. Ignition switch OFF.

      2. Disconnect BCM connector.

      3. Check continuity between BCM harness connector and ground.

         Front turn signal lamp

         BCM			—	Continuity
         Connector		Terminal
         RH	M142	116	Ground	No
         LH		128

         Side turn signal lamp

         BCM			—	Continuity
         Connector		Terminal
         RH	M84	1	Ground	No
         LH		21

         Rear turn signal lamp

         BCM			—	Continuity
         Connector		Terminal
         RH	M21	159	Ground	No
         LH		151

   Is the inspection result normal?

   YES >>

   Replace BCM. Refer to Removal and Installation.

   NO >>

   Repair or replace harness.

7. CHECK TURN SIGNAL LAMP POWER SUPPLY CIRCUIT (OPEN)

   1. 1. Ignition switch OFF.

      2. Disconnect BCM connector.

      3. Check continuity between BCM harness connector and each turn signal lamp harness connector.

         Front turn signal lamp

         BCM			Front combination lamp		Continuity
         Connector		Terminal	Connector	Terminal
         RH	M142	116	E38	2	Yes
         LH		128	E37

         Side turn signal lamp (with Intelligent Around View® Monitor)

         BCM			Door mirror		Continuity
         Connector		Terminal	Connector	Terminal
         RH	M84	1	D106	11	Yes
         LH		21	D7

         Side turn signal lamp (with Intelligent Around View® Monitor)

         BCM			Door mirror		Continuity
         Connector		Terminal	Connector	Terminal
         RH	M84	1	D113	1	Yes
         LH		21	D4

         Rear turn signal lamp

         BCM			Rear combination lamp (body side)		Continuity
         Connector		Terminal	Connector	Terminal
         RH	M21	159	B42	1	Yes
         LH		151	B25

   Is the inspection result normal?

   YES >>

   GO TO 8.

   NO >>

   Repair or replace harness.

8. CHECK TURN SIGNAL LAMP GROUND CIRCUIT

   1. Check continuity between each turn signal lamp harness connector and ground.

      Front turn signal lamp

      Front combination lamp			—	Continuity
      Connector		Terminal
      RH	E38	1	Ground	Yes
      LH	E37

      Side turn signal lamp (with Intelligent Around View® Monitor)

      Door mirror			—	Continuity
      Connector		Terminal
      RH	D106	12	Ground	Yes
      LH	D7

      Side turn signal lamp (without Intelligent Around View® Monitor)

      Door mirror			—	Continuity
      Connector		Terminal
      RH	D113	5	Ground	Yes
      LH	D4

      Rear turn signal lamp

      Rear combination lamp (body side)			—	Continuity
      Connector		Terminal
      RH	B42	4	Ground	Yes
      LH	B25

   Is the inspection result normal?

   YES >>

   Front turn signal lamp: Replace corresponding front combination lamp bulb. Refer to Bulb Replacement.

   YES >>

   Rear turn signal lamp: Replace corresponding rear combination lamp (body side) bulb. Refer to Bulb Replacement.

   YES >>

   Side turn signal lamp: Replace corresponding door mirror turn signal lamp. Refer to Removal and Installation.

   NO >>

   Repair or replace harness.

© 2014-2026 Copyright www.nisentra.com