Nissan Sentra B18 (2020-2025) Service Manual: Dtc Diagnosis Procedure

DTC Diagnosis Procedure

1. CHECK FUSE

   1. 1. Ignition switch OFF.

      2. Check that the following fuse is not blown (open):

         Signal name	Fuse No.	Capacity
         Ignition switch ON power supply	6	10 A

   Is the inspection result normal?

   YES >>

   GO TO 2

   NO >>

   Replace the blown fuse after repairing the affected circuit.

2. CHECK HEATED SEAT LH HIGH RELAY POWER SUPPLY

   1. 1. Disconnect heated seat LH high relay connector.

      2. Ignition switch ON.

      3. Check voltage between heated seat LH high relay harness connector and ground.

         (+)		(-)	Voltage (Approx.)
         Heated seat LH high relay
         Connector	Terminal
         M150	1	Ground	Battery voltage

   Is the inspection result normal?

   YES >>

   GO TO 3.

   NO >>

   Repair or replace harness.

3. CHECK HEATED SEAT LH HIGH RELAY

   1. Check heated seat LH high relay.

      Refer to Component Inspection.

   Is the inspection result normal?

   YES >>

   GO TO 4.

   NO >>

   Replace heated seat LH high relay.

4. CHECK HEATED SEAT LH HIGH RELAY CONTROL SIGNAL

   1. 1. Connect heated seat LH high relay connector.

      2. Check voltage between A/C auto amp. (with auto A/C) or A/C amp. (with manual A/C) harness connector and ground.

         With auto A/C

         (+)		(–)	Condition		Voltage (Approx.)
         A/C auto amp.
         Connector	Terminal
         M34	55	Ground	Heated seat switch LH (HIGH)	OFF	Battery voltage
         				ON	0 V

         With manual A/C

         (+)		(–)	Condition		Voltage (Approx.)
         A/C amp.
         Connector	Terminal
         M82	55	Ground	Heated seat switch LH (HIGH)	OFF	Battery voltage
         				ON	0 V

   Is the inspection result normal?

   YES >>

   Replace A/C auto amp. (with auto A/C) or A/C amp. (with manual A/C). Refer to Removal and Installation (with auto A/C) or Removal and Installation (with manual A/C).

   NO >>

   GO TO 5.

5. CHECK HEATED SEAT LH HIGH RELAY CONTROL SIGNAL CIRCUIT

   1. 1. Ignition switch OFF.

      2. Disconnect A/C auto amp. connector (with auto A/C) or A/C. amp. connector (with manual A/C) and heated seat LH high relay connector.

      3. Check continuity between A/C auto amp. harness connector (with auto A/C) or A/C. amp. harness connector (with manual A/C) and heated seat LH high relay harness connector.

         With auto A/C

         A/C auto amp.		Heated seat LH high relay		Continuity
         Connector	Terminal	Connector	Terminal
         M34	55	M150	2	Yes

         With manual A/C

         A/C amp.		Heated seat LH high relay		Continuity
         Connector	Terminal	Connector	Terminal
         M82	55	M150	2	Yes

      4. Check continuity between A/C auto amp. harness connector (with auto A/C) or A/C amp. harness connector (with manual A/C) and ground.

         With auto A/C

         A/C auto amp.		(–)	Continuity
         Connector	Terminal
         M34	55	Ground	No

         With manual A/C

         A/C amp.		(–)	Continuity
         Connector	Terminal
         M82	55	Ground	No

   Is the inspection result normal?

   YES >>

   GO TO 6.

   NO >>

   Repair or replace harness.

6. CHECK INTERMITTENT INCIDENT

   1. Check intermittent incident.

      Refer to Intermittent Incident.

   >>

   Inspection End.

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