2021-2024 Jeep Wrangler / Gladiator Service 4WD Message TSB

Symptoms of the "Service 4WD Message"

Owners of 2021-2024 Jeep Wrangler and Gladiator vehicles may experience the "Service 4WD Message" appearing on the instrument cluster, along with the illumination of the 4-wheel drive warning lamp. This indicates a potential problem within the vehicle's 4-wheel drive system. Technicians have observed this symptom alongside specific Diagnostic Trouble Codes (DTCs) related to the front axle and transfer case components.

Diagnostic Trouble Codes (DTCs)

When the "Service 4WD Message" appears, technicians often find one or more of the following DTCs stored in the vehicle's system. These codes help pinpoint the area of concern within the electrical system.

Diagnosis and Repair Procedure Summary

Technical Service Bulletin S2008000084 REV. C, released in February 2025, outlines a diagnostic and repair procedure focusing on wiring integrity. If any of the listed DTCs are active or stored, technicians are instructed to inspect specific wiring locations for potential issues. The primary focus is on identifying and rectifying wiring concerns that could lead to the "Service 4WD Message".

The repair procedure involves several key inspection points:

• Front Axle Disconnect (FAD) Connector: Technicians should review the FAD connector for proper seating. This includes checking for any pins that are not fully seated, signs of wiring rubbing against the connector dress, water ingress, debris, or corrosion. Figure 1 in the bulletin illustrates how a wire loom might not be properly secured to the connector, allowing wire contact.
• Upper Control Arm Clip Wiring: The wiring near the upper control arm clip needs to be inspected. Technicians will look for tight clips or wires underneath the convolute that show damage or rubbing. Figure 2 provides an example of a wire break found behind an upper zip-tie in this area.
• Frame Clipping Points: Wiring at various clipping points on the vehicle frame should be examined for rubbing damage. This also includes verifying that clips are fully inserted into the frame and that straps are not excessively tight.
• Ground G916A: A critical step is to review Ground G916A for proper attachment and any signs of corrosion. Figure 3 provides a diagram of the ground topology, highlighting the location of G916A, particularly for Jeep Wrangler Pickup (JT) models.

After inspection, any suspect locations found to have wiring concerns, such as rubbing, damage, or corrosion, must be cleaned, repaired, and securely reattached. This comprehensive inspection aims to resolve the underlying electrical issues causing the "Service 4WD Message".

Important Warnings for Owners

It is crucial for owners to understand that this document, Technical Service Bulletin S2008000084 REV. C, does not authorize warranty repairs directly. This communication serves as a record of past experiences and known cases that appear similar or related to the vehicle symptom. It does not provide definitive conclusions about what is wrong with every specific vehicle, but rather guides technicians in their diagnostic process. You are the expert, and you are responsible for deciding on the appropriate course of action.

What Owners Should Do

If your 2021-2024 Jeep Wrangler or Gladiator displays the "Service 4WD Message" or the 4-wheel drive warning lamp is illuminated, it is recommended to have your vehicle inspected by a qualified service technician. They will be able to diagnose the specific cause using the guidance provided in TSB S2008000084 REV. C and address any underlying wiring issues.

Source: NHTSA ID: 11014264