Diagnosis Procedure

WARNING: This page is about a different car, the 2008 Nissan Titan. 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: Go to "WIRING DIAGRAM ".

CHECK HORN RELAY POWER SUPPLY

Turn ignition switch ON.
Perform "ACTIVE TEST", "HORN" with CONSULT-Ill.
Using an oscilloscope or analog voltmeter, check voltage between horn relay harness connector and ground.

Fig 1: Identifying Voltage Between Horn Relay Harness Connector And Ground

Courtesy of NISSAN MOTOR CO., U.S.A.

VOLTAGE REFERENCE CHART

Horn relay		Ground	Test item		Voltage (V) (Approx.)
Connector	Terminal	Ground	Test item		Voltage (V) (Approx.)
H-1	1	Ground	HORN	ON	Battery voltage → 0 → Battery voltage
H-1	1	Ground	HORN	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.

Fig 2: Identifying Continuity Between IPDM E/R Connector E122 Terminal 45 And Connector H-1 Terminal 1

Courtesy of NISSAN MOTOR CO., U.S.A.

CONTINUITY SPECIFIED CONDITIONS

IPDM E/R		Horn relay		Continuity
Connector	Terminal	Connector	Terminal	Continuity
E122	45	H-1	1	Yes

Check continuity between IPDM E/R harness connector and ground.

CONTINUITY SPECIFIED CONDITIONS

IPDM E/R		Ground	Continuity
Connector	Terminal	Ground	Continuity
E122	45	Ground	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 OF IPDM E/R ".

No: Repair or replace the malfunctioning part.