Technical Service Bulletins

Transmission wrangling

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Transmission wrangling



Owners of 2010 Jeep Wrangler vehicles (equipped with the 3.8L engine and 42RLE transmission (built before Nov. 3, 2009) may note that the transmission remains in the “Default” mode (second gear) after and engine start, and the transmission will not shift into a higher gear.

This condition may be intermittent. If the engine is turned off and restarted, the transmission will often perform normally. There will be no transmission related DTCs present.

The “Default” mode is used to protect the transmission. The transmission logic will remain in or revert to this mode if certain operating parameters are not met in a specified time during engine start.

If this condition is present, a reflash is required.

  1. Reprogram the PCM with the latest software (wiTECH software level must be at release 10.01 or higher). Follow the detailed service procedures available in DealerCONNECT/TechCONNECT. Refer to Group 8 – Electrical > Electronic Control Modules – Service Information > Module – Powertrain Control > Standard Procedures > PCM/ECM Programming – Gas.
  2. After PCM reprogramming, clear any DTCs that may have been set in other modules due to reprogramming. The wiTECH application will automatically present all DTCs after the flash and allow the tech to clear them.
  3. Type the necessary information on an Authorized Modification Label and attach it near the VECI label.

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