WenmarOpen by Wenmar Pro

Service bulletin 21-026-15

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10057945
Published by NHTSA2015-07-16
Manufacturer's number21-026-15
Manufacturer's date2015-04-21
NHTSA componentPOWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM)

NHTSA's summary

CHRYSLER 2014-2015 JEEP WRANGLER: INFORMATION REGARDING TRANSMISSION CONTROL MODULE AVAILABLE SOFTWARE. CUSTOMERS ARE EXPERIENCING DELAYED SHIFT RESPONSE WHEN DRIVING UP HILLS, VIBRATION ON ACCELERATION FROM A CRUISING SPEED. *LJ

The document

No address for NHTSA's copy can be built for this communication. Ask the dealer for it by the manufacturer's number.

Components

Transmission and driveline, Automatic transmission, Transmission control module

Vehicles listed
JEEP WRANGLER2014, 2015

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Other bulletins for the same vehicles and component
18068142023-02-21. Service bulletin. U0140 Lost Communication With Body Control Module
V512022-12-19. Service bulletin. Customer Satisfaction Notification V51 Reprogram Powertrain Control Module
RL156209A$2022-07-25. Service bulletin. Part Description: Transmission Issue Description: If the vehicle you are repairing exhibits a whine/whistle noise when traveling at low speeds or when shifting into gear please call Jian Zhu on his cell at (248) 379-1132 prior to replacing the transmission. Jian is looking to get information. Also, Engineering would like to visit a dealers located in the SE Michigan area with a vehicle exhibiting the above complaint. If Jian cannot be reached within 15 minutes proceed with the repair.
V512020-01-21. Service bulletin. Customer Satisfaction Notification V51 Reprogram Powertrain Control Module
18-024-152018-09-24. Service bulletin. Flash: U0140 Lost Communication With Body Control Module This bulletin involves reprogramming the Powertrain Control Module (PCM) with update software. During normal diagnostics a technician may find Diagnostic Trouble Code (DTC) U0140 Lost Communication With Body Control Module. Attempting to clear the DTC will be unsuccessful.
21-023-142018-06-18. Service bulletin. Flash: Transmission Shift Enhancements This bulletin involves flash reprogramming of the Transmission Control Module (TCM) with new software. The following Transmission Control Module (TCM) calibration improvements are available for vehicles equipped with WA580 Automatic Transmission (Sales Code DGJ).3.6L Wrangler Transmission shifting does not meet customers expectation while towing a loaded trailer in high ambients (>32°C/90°F). Poor performance and/or poor powertrain response when trying to accelerate from speeds >48 kph (30 mph) - Japan/Taiwan/China vehicles only. Rubicon Only.2.8L Wrangler Transmission shifts inconsistently (gear hunting) when driving up/down steep hills or when towing a trailer. Delayed Drive to Reverse shift engagement when the transfer case is in Low Range (4LO) Transmission shifting while accelerating from a stop does not meet customers expectation. Poor vehicle performance in Drive Poor vehicle performance in Auto Stick Mode. Rubicon Only.
18-029-142018-06-11. Service bulletin. Flash: MIL Illumination. Includes Powertrain System Improvements/Enhancements This bulletin involves selectively erasing and reprogramming the Powertrain Control Module (PCM) with new software. A small number of customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the Technician may find that the following Diagnostic Trouble Codes have been set: ? P2097- Downstream Fuel Trim System 1 Rich ? P2099- Downstream Fuel Trim System 2 Rich The following powertrain system improvements/enhancements are also included in this software release: ? Corrected a generic scan tool display issue regarding Mode 6 data accuracy. Updating the PCM software will correct the conditions listed above.
08-043-142018-05-21. Service bulletin. Cruise Control System Slow To Respond To Cruise Control Switch Inputs This bulletin involves upgrading the software in the Powertrain Control Module (PCM). A customer may experience, slow response to cruise control switch activations.
18-003-142018-05-21. Service bulletin. Flash: Unable to Program Keys After Wireless Control Module Replacement and/or Malfunction Indicator Lamp (MIL) Illumination This bulletin involves selectively erasing and reprogramming the Powertrain Control Module (PCM) with new software. Technicians may find that the original vehicle keys/FOBIKs do not function properly following replacement of the Wireless Control Module(WCM). The Secret Key information stored in the PCM may be corrupt. This update will restore the PCM?s ability to store/transfer valid Secret Key information.A small number of customers may also experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the Technician may find that the following Diagnostic Trouble Code (DTC) has been set: P0606 - Internal Control ProcessorIf the WCM had been replaced prior to this software update, the original keys/FOBIKs will need to be replaced.
18-041-16 REV. A2017-11-03. Service bulletin. Flash: Powertrain Diagnostic And System Enhancements This bulletin involves reprogramming the Powertrain Control Module (PCM) with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find that one of the following Diagnostic Trouble Codes (DTCs) have been set: · **P0300 - Multiple Cylinder Misfire (3.6L Engine Sales Code ERB only). · P0306 - Cylinder 6 Misfire (Automatic Transmissions only).** · P0335 - Crankshaft Position Sensor Circuit. · P0456 - EVAP System Small Leak (3.6L Engine Sales Code ERB only). · U0140 - Lost Communication With Body Control Module.