2024 Jeep Wrangler PCM Update for O2 Sensor DTCs

Symptoms

Owners of affected 2024 Jeep Wrangler vehicles may experience a variety of symptoms, often accompanied by a Malfunction Indicator Lamp (MIL) illumination. These include:

• Malfunction Indicator Lamp (MIL) illumination
• Vehicle runs rough.
• "Service Transmission” message displayed in the Instrument Panel Cluster (IPC) due to clutch slip detection with the transfer case in neutral.
• Transfer case mis-shift during flat tow (engine running and clutch pedal up, transmission in gear).

Fault Codes / DTCs

The MIL illumination will typically be accompanied by one or more of the following Diagnostic Trouble Codes (DTCs):

Code	Description
P0032	O2 - Sensor 1/1 Heater Circuit High
P0038	O2 - Sensor 1/2 Heater Circuit High
P0052	O2 - Sensor 2/1 Heater Circuit High
P0058	O2 - Sensor 2/2 Heater Circuit High
P1129	Closed Loop Fueling Not Achieved-Banks 2 Upstream
P0152	O2 Sensor 2/1 Circuit High
P0158	O2 Sensor 2/2 Circuit High
P2504	Charging System Output High
P0563	System Voltage High

Diagnosis / Trigger Conditions

Diagnosis for these issues involves verifying the presence of a Malfunction Indicator Lamp (MIL) illumination and one or more of the listed DTCs. Technicians will use a Scan Tool (wiTECH) to confirm related systems are functioning correctly. If any symptoms or DTCs not covered by this bulletin are present, they should be addressed first.

Repair Procedure Summary

This Technical Service Bulletin (TSB) 18-050-24 REV. A involves updating the Powertrain Control Module (PCM) software. The procedure is as follows:

1. Verify if the vehicle's VIN is on the Rapid Service Update (RSU) list. If so, proceed with the update. If not, but the vehicle exhibits the symptoms, the update should still be performed.
2. Check if the PCM already has the latest software installed. If it does, the bulletin is complete.
3. Reprogram the PCM with the latest available software using the wiTECH Diagnostic Application. If issues arise during flashing, a ticket should be submitted to the Helpdesk.
4. After reprogramming, check if any of the O2 sensor DTCs (P0032, P0052, P0058, P0038) return. If they do, further DTC diagnostics and repair procedures are required.
5. Clear all DTCs that may have been set in any module due to the reprogramming process. The wiTECH application will automatically present and allow clearing of these codes.

This bulletin supersedes previous versions, TSB 18-050-24 dated May 21, 2024, and TSB 08-142-24 dated June 19, 2024. This update has also been released as Rapid Service Update (RSU) 24-109.

Required Tools or Parts

To perform this 2024 Jeep Wrangler PCM update, a wiTECH scan tool or equivalent diagnostic equipment is required.

Important Warnings

During the PCM reprogramming process, it is crucial to install a battery charger. This ensures the battery voltage does not drop below 13.2 volts. Technicians must also ensure the charging voltage does not climb above 13.5 volts during the flash process. If the flash process is interrupted or aborted, it should be restarted.

Owner Action

If your 2024 Jeep Wrangler is experiencing any of the symptoms described, such as MIL illumination, rough running, or a "Service Transmission" message, you should contact your authorized Jeep dealer. All repairs performed under this Technical Service Bulletin are reimbursable within the provisions of your vehicle's warranty.

NHTSA ID: 11005721