Diagnosis Procedure
WARNING: This page is about a different car, the 2019 Nissan NV3500 HD, 2019 Nissan NV2500 HD, and 2019 Nissan NV1500. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK HORN FUNCTION
Check horn function with horn switch
Do the horns sound?
YES
GO TO 2.
NO
Refer to appropriate system Wiring Diagram.
- CHECK HORN RELAY POWER SUPPLY
- Turn ignition switch ON.
- Perform ACTIVE TEST, HORN with CONSULT.
- Using an oscilloscope or analog voltmeter, check voltage between horn relay harness connector and ground.
Horn relay
Ground
Test item
Voltage (V) (approx.)
Connector
Terminal
H-1
1
Ground
HORN
ON
Battery voltage -> 0 -> Battery voltage
Other than above
Battery voltage
Is the inspection result normal?
YES
GO TO 4.
NO
GO TO 3.
- CHECK HORN RELAY CIRCUIT
- Turn ignition switch OFF.
- Disconnect IPDM E/R and horn relay connector.
- Check continuity between IPDM E/R harness connector and horn relay harness connector.
IPDM E/R
Horn relay
Continuity
Connector
Terminal
Connector
Terminal
E122
45
H-1
1
Yes
- Check continuity between IPDM E/R harness connector and ground.
IPDM E/R
Ground
Continuity
Connector
Terminal
E122
45
No
Is the inspection result normal?
YES
GO TO 4.
NO
Repair or replace harness.
- CHECK INTERMITTENT INCIDENT
Refer to Intermittent Incident .
Is the inspection result normal?
YES
Replace IPDM E/R. Refer to Removal and Installation .
NO
Repair or replace the malfunctioning part.