Horn

Replace or diagnose the horn assembly on a 1992 Dodge Viper, including access through the front fascia, electrical testing, and proper mounting.

Warnings

Tools required

Parts

• Horn assembly × 1 — Mopar 4720150 or equivalent

Preparation

1. Park vehicle on level surface and apply parking brake
2. Place wheel chocks behind rear wheels
3. Disconnect battery negative terminal and wait 2 minutes for airbag system capacitor discharge
4. Raise front of vehicle and support securely on jack stands
5. Allow engine to cool completely if recently driven

Procedure

1. 1

   Access horn location from underneath
   From underneath the vehicle on the driver side, locate the horn assembly mounted to the frame rail behind the front fascia, approximately 12 inches back from the front of the radiator support. The horn is a disc-shaped component with an electrical connector and single mounting bracket.
2. 2

   Disconnect horn electrical connector
   Press the locking tab on the horn electrical connector and pull straight off the horn terminals. Note the connector orientation for reinstallation. If testing the existing horn, use a multimeter to verify 12V power at the connector when horn button is pressed (requires assistant). Note: Disconnect battery negative terminal before working on horn circuit to prevent short circuits
3. 3

   Remove horn mounting fastener
   Using a 13mm socket, remove the single bolt securing the horn bracket to the frame rail. Support the horn assembly as you remove the bolt to prevent it from falling.
4. 4

   Remove horn assembly
   Lower the horn assembly away from the frame rail and maneuver it out from behind the fascia. Inspect the mounting bracket for damage or corrosion. If the horn is being tested rather than replaced, bench test it by applying 12V directly to the terminals with jumper wires to verify operation.
5. 5

   Inspect mounting location and clean surfaces
   Inspect the frame rail mounting point for corrosion or damage. Clean the mounting surface with a wire brush if rust or corrosion is present. Verify the horn ground path is clean and free of paint or corrosion where the bracket contacts the frame.
6. 6

   Install horn assembly
   Position the new or tested horn assembly with bracket against the frame rail mounting point. Ensure the horn terminals face toward the connector access point. Thread the mounting bolt by hand to ensure proper alignment.
7. 7

   Torque horn mounting bolt
   Using a torque wrench and 13mm socket, tighten the horn mounting bolt to 15 Nm (11 lb-ft). Verify the horn assembly is secure and does not rotate on the bracket.
   Torque spec

   Horn Mounting Bolt15 Nm (11 lb-ft)
8. 8

   Reconnect electrical connector
   Push the electrical connector firmly onto the horn terminals until the locking tab clicks into place. Tug gently on the connector to verify it is fully seated and locked.
9. 9

   Lower vehicle and reconnect battery
   Lower the vehicle from jack stands. Reconnect the battery negative terminal and torque to 7.0 Nm (5 lb-ft) using a 10mm socket and torque wrench.
   Torque spec

   Battery Terminal Bolts7 Nm (5 lb-ft)

Reassembly

1. Ensure horn electrical connector is fully seated and locked before testing
2. Verify horn mounting bolt is torqued to specification to ensure proper ground contact
3. Battery terminal must be clean and torqued properly to avoid electrical issues

Verification

• With battery reconnected and vehicle in Park, press the horn button on the steering wheel to verify horn sounds
• Listen for full volume output without buzzing or weak tone
• Verify horn stops immediately when button is released
• Check that no warning lights appear on the instrument cluster related to airbag system after battery reconnection

More procedures for this vehicle