2023-2026 Jeep, Ram, Dodge Horn Malfunction TSB

Owners of certain 2023-2026 Jeep, Ram, and Dodge vehicles may experience issues with their vehicle's horn, ranging from a weak sound to complete inoperation. Stellantis has issued Technical Service Bulletin (TSB) S2423000027 Rev. D, released in February 2026, to guide technicians in diagnosing and resolving these horn-related concerns.

This TSB specifically addresses customer complaints where the "Horn Sound Is Weak, Off Tone, Inoperative, Or Intermittent," or when the "Owner complains the horns do not sound correct or work." The diagnostic process aims to identify the root cause of the horn malfunction, ensuring proper function and safety.

Symptoms

Vehicle owners might notice one or more of the following symptoms related to their horn system:

• The horn produces a sound that is noticeably weaker than usual.
• The horn's tone is incorrect or "off-tone."
• The horn operates intermittently, sometimes working and sometimes not.
• The horn is completely inoperative and does not sound at all.

Important Warnings

Stellantis provides crucial guidance for technicians to prevent further damage during diagnosis:

• No Warranty Authorization: This document does not authorize warranty repairs. It serves as a record of past experiences and does not provide conclusions about what is wrong with a specific vehicle.
• Probing Terminals: Technicians must "never face or back probe terminals to avoid pin damage." Instead, the Test Lead Kit 2064100081 should be used for probing.

Diagnostic Procedure Summary

Technicians are advised to follow a detailed diagnostic process to address the horn malfunction. This process begins with a preliminary check and progresses through various electrical system components.

1. Initial Assessment: Record any Diagnostic Trouble Codes (DTC) present on the repair order and perform diagnostics. If the issue is unresolved, disconnect the negative battery cable for two minutes to allow for capacitor discharge. Reconnect the battery and retest the horn operation. If the horn(s) remain inoperative, further steps are required.

2. Fuse Inspection: Verify that the appropriate fuse in the Power Distribution Center (PDC) is not open and is correctly installed. The specific fuse varies by model:

   • Ram 1500 (DT): F40 20 A
   • Ram 2500 (DJ), 3500 (DD D2), 4500 5000 (DP), Dodge Durango (WD): F42 20 A
   • Jeep Compass (MP): F65 20 A
   • Jeep Grand Cherokee (WL), Wagoneer (WS): F66 20 A
   • Jeep Wagoneer S (KM): F34 20 A
   • Jeep Wrangler (JL), Gladiator (JT): F91 20 A
   • Promaster (VF): F10 15 A

3. Horn Bench Test: Turn off the ignition and disconnect the horns. Bench test them using a terminal test kit. Ensure the horns operate between 9.3V and 16V, ideally at 13V, with a maximum current draw of 6 amps for a single horn or 12 amps for dual horns. Note that "Horn tones weaken when the battery voltage is low." If the horn works, proceed to the next step. If not, replace the inoperative horn.

4. Connector and Harness Inspection: Disconnect all harness connectors from the Power Distribution Center (PDC), Body Control Module (BCM), or Steering Column Control Module (SCCM) for the circuit being tested. Inspect these connectors, components, and terminals for:

   • Proper connector installation.
   • Damaged connector locks, corrosion, or signs of water intrusion.
   • Bent terminals.
   • Overheating indicated by discolored terminals due to poor connection.
   • Terminals pushed into the connector cavity.
   • Perform a terminal drag test to check terminal tension.

5. DTC Re-check and Module Replacement: Reconnect all harness connectors, clear any DTCs with a scan tool, and operate the vehicle under conditions that would trigger the horn issue. Check for current BCM or SCCM-related DTCs. If present, replace the affected assembly (PDC, BCM, or SCCM).

6. Clock Spring and Horn Switch Check: If the horn sounds while turning or driving, inspect the Clock Spring in the SCCM for a possible short circuit, provided the wiring is in good condition. For the horn switch, verify its proper operation by following service instructions 08 - Electrical / 8H - Horn / SWITCH, Horn / Diagnosis and Testing. It's important to note that "The horn switch is part of the Driver Airbag (DAB), non-repairable. Replace the entire DAB if faulty or damaged."

7. Voltage and Ground Checks: As a final option, turn on the ignition and refer to the Service Library wiring diagram for the horn circuit. With an assistant pressing the horn button, use a Digital Volt-Ohm Meter to measure voltage from the PDC relay output to the horn. Also, check the ground at the BCM low current relay coil harness connectors.

   • If voltage is present, check and repair the circuit for a voltage short.
   • If no voltage, check the PDC harness for open circuit or connection issues.
   • If continuity to ground is present, check and repair the circuit for a ground short.
   • If no continuity to ground, check the BCM harness connections for issues.

This comprehensive approach helps diagnose the root cause of a "Jeep Wrangler horn malfunction" and ensures proper repair.

Required Tools or Parts

• Test Lead Kit 2064100081: This specialized kit is required for probing terminals to avoid damage during diagnostic procedures.

Owner Action

If you are experiencing a weak, off-tone, inoperative, or intermittent horn in your 2023-2026 Jeep, Ram, or Dodge vehicle, it is recommended to schedule an appointment with an authorized Stellantis dealership. Their technicians are equipped with the necessary tools and information, including TSB S2423000027 Rev. D, to accurately diagnose and resolve the horn system issue.

NHTSA ID: S2423000027