2021-2026 Jeep/RAM/Dodge Service Transmission Warning TSB

Symptoms of Transmission Warning Indicator

Owners of certain 2021-2026 Jeep, RAM, and Dodge vehicles may notice a "Service transmission" or "check engine" warning indicator illuminating on their dashboard. This issue affects vehicles equipped with 850RE, 8HP50, 8HP70, 8HP75, and 8HP75-PHEV 8-speed transmissions. The presence of these warning lights signals that the vehicle's powertrain control module has detected a fault within the transmission system, requiring attention.

Fault Codes / DTCs

When the "Service transmission" or "check engine" warning appears, it is typically accompanied by specific Diagnostic Trouble Codes (DTCs) stored in the vehicle's computer. These codes help technicians pinpoint the nature of the issue. The following fault codes are associated with this particular problem, indicating a need for further diagnosis and repair as outlined in TSB S2621000003:

Code	Description
P07E4	Transmission related fault
P1DB2	Transmission related fault
P0716	Transmission related fault
P1B14	Transmission related fault
P0733	Transmission related fault
P1D90	Transmission related fault
P1DB7	Transmission related fault
P1B13	Transmission related fault

Diagnosis and Trigger Conditions

Diagnosing the root cause of a "Service transmission" or "check engine" warning, especially when accompanied by a Jeep RAM Dodge transmission P07E4 code, requires careful evaluation. Stellantis Technical Service Bulletin S2621000003 clarifies several important diagnostic considerations.

Firstly, the smell of burnt fluid in an 8-speed transmission is often due to the fluid's high sulfur content and is not, by itself, a reliable symptom to authorize a transmission replacement. Similarly, a visual inspection of the transmission fluid in the oil pan is subjective and typically does not indicate a gearbox issue. Normal wear of a transmission can produce fine metallic particles; this should only be considered an indicator of internal transmission damage or replacement in extreme cases.

If any of the listed fault codes (P07E4, P1DB2, P0716, P1B14, P0733, P1D90, P1DB7, P1B13) are found to be active or stored, technicians should proceed with the repair procedure. A specific check is required for codes P1B13 and P1B14: ensure the MPR cable is not slightly applied or stuck, as this could be a contributing factor to the Jeep RAM Dodge transmission P07E4 issue or related codes.

Important Warnings for Technicians and Owners

This communication, TSB S2621000003, serves as a record of past experiences and does not authorize warranty repairs based solely on its content. It's crucial to understand that the information provided documents previous cases and does not offer conclusions about what is definitively wrong with every vehicle. Technicians are responsible for their expertise and for deciding the appropriate course of action based on comprehensive diagnostics.

Repair Procedure Summary

For vehicles exhibiting the "Service transmission" or "check engine" warning with the associated fault codes, the primary repair strategy involves specific steps. The initial and preferred repair option is a Valve Body replacement. This procedure should be considered before a complete transmission replacement, unless there is clear and significant existing gearbox damage. If the transmission concerns persist after the valve body has been replaced, further diagnostics are necessary.

Technicians must record all fault codes present in a fresh Scan Report after the valve body replacement. Additionally, any further diagnostics related to new codes or shift quality concerns should be performed, and the results meticulously documented. This systematic approach ensures that the underlying cause of the Jeep RAM Dodge transmission P07E4 or other related codes is thoroughly addressed.

Required Tools or Procedures

To properly diagnose and address the transmission issues outlined in TSB S2621000003, specific documentation and procedures are required:

• Transmission Diagnostic Worksheet: This worksheet must be fully completed for all cases.
• Transmission Shift Quality Worksheet: For any cases involving shift quality concerns, this worksheet must also be thoroughly completed.
• Documentation for STAR Ticket: When submitting a STAR ticket or request to PTSC, technicians must attach clear and concise pictures. These pictures should show any damage, debris in the pan, and the condition of the fluid.

Owner Action

If your 2021-2026 Jeep, RAM, or Dodge vehicle is displaying a "Service transmission" or "check engine" warning indicator, especially with fault codes like P07E4, it is recommended to have your vehicle inspected by a qualified service technician. Provide them with details about the symptoms you've observed. While this is a manufacturer communication, not a recall, addressing these issues promptly can prevent further transmission damage and ensure the longevity and safe operation of your vehicle.

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Source: NHTSA ID: 11029770