Check Horn Circuit

CHECK HORN CHIRP FUNCTION
With CONSULT-II
1. Check horn function "HORN" in "ACTIVE TEST" mode with CONSULT-II.
2. Perform operation shown on display.
  1. Horn should sound.
  Fig 1: ACTIVE TEST - CONSULT II Display
  Courtesy of NISSAN MOTOR CO., U.S.A.
Without CONSULT-II
1. Turn ignition switch OFF.
2. Disconnect BCM connector.
3. Apply ground to BCM connector E204 terminal 127.
  1. Horn should sound.
OK or NG
1. OK: Horn alarm is OK.
2. NG: GO TO 2.
Fig 2: Identifying BCM Connector E204 Terminal 127
Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK HORN RELAY
Check horn relay condition.

OK or NG
1. OK: GO TO 3.
2. NG: Replace horn relay.
CHECK POWER SUPPLY FOR HORN RELAY
1. Turn ignition switch OFF.
2. Disconnect horn relay connector.
3. Check voltage between horn relay connector E3-5 terminal 2 and ground.
  1. 2 - Ground: Battery voltage.
OK or NG
1. OK: GO TO 4.
2. NG: Check the following.
  - 15A fuse [No. 56, located in the fuse, fusible link and relay block (J/B)]
  - Harness for open or short between horn relay and fuse
Fig 3: Checking Voltage Between Horn Relay Connector E3-5 Terminal 2 And Ground
Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK HORN RELAY CIRCUIT
1. Disconnect BCM connector.
2. Check continuity between BCM connector E204 terminal 127and horn relay connector E3-5 terminal 1.
  1. 127 (G/W) - 1 (G/W): Continuity should exist.
OK or NG
1. OK: GO TO 5.
2. NG: Repair or replace harness.
Fig 4: Checking Continuity Between BCM Connector E204 Terminal 127 And Horn Relay Connector E3-5 Terminal 1
Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK HORN RELAY CIRCUIT
1. Disconnect horn relay and horn high or low connector.
2. Check continuity between horn relay connector E3-5 terminal 3 and horn connector E43 (low), E63 (high) terminal 1.
  1. LOW
  2. 3 - 1 (G): Continuity should exist.
  3. HIGH
  4. 3 - 1 (G/OR): Continuity should exist.
OK or NG
1. OK: GO TO 6.
2. NG: Repair or replace harness.
Fig 5: Checking Continuity Between Horn Relay Connector E3-5 Terminal 3 And Horn Connector E43 (Low), E63 (High) Terminal 1
Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK HORN AND HORN GROUND
Apply battery voltage to horn terminal 1.

Horn should sound.

OK or NG
1. OK: Replace BCM.
2. NG: Replace horn or repair horn ground.