WenmarOpen by Wenmar Pro

Service bulletin 18-071-26 REV. A

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 id11038312
Published by NHTSA2026-10-07
Manufacturer's number18-071-26 REV. A
Manufacturer's date2026-10-03
NHTSA componentPOWER TRAIN

NHTSA's summary

Flash: Powertrain Control Module (PCM) Updates Customers may experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle may SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● **P2237-00 - O2 Sensor Positive Current Control Circuit/Open Bank 1 Sensor 1. ● P2240-00 - O2 Sensor Positive Current Control Circuit/Open Bank 2 Sensor 1. ● P2251-00 - O2 Sensor Negative Current Control Circuit/Open Bank 1 Sensor 1. ● P2254-00 - O2 Sensor Negative Current Control Circuit/Open Bank 2 Sensor 1. ● P2243-00 - O2 Sensor Reference Voltage Circuit/Open Bank 1 Sensor 1. ● P2247-00 - O2 Sensor Reference Voltage Circuit/Open Bank 2 Sensor 1. ● P015B-00 - O2 Sensor Delayed Response - Lean To Rich Bank 1 Sensor 1. ● P015D-00 - O2 Sensor Delayed Response - Lean To Rich Bank 2 Sensor 1. ● P0E7C-00 - Coolant Bypass Valve "B" Control Circuit Low. ● P0E7D-00 - Coolant Bypass Valve "B" Control Circuit High. ● P0E7E-00 - Coolant Bypass Valve "B" Control Circuit Range/Performance. ● P0E7F-00 - Coolant Bypass Valve "B" Control Circuit Stuck/Open. ● U063C-00 - Lost Communication With Coolant Bypass Valve Actuator "B". ● P0100-00 - Mass Or Volume Air Flow Sensor "A" Circuit. ● P0101-00 - Mass Or Volume Air Flow Sensor "A" Circuit Range/Performance. ● P0461-00 - Fuel Level Sensor "A" Circuit Range/performance. ● P0072-00 - Ambient Air Temperature Sensor Circuit "A" Low. ● P062B-00 - Internal Control Module Fuel Injector Control Performance. ● B1810-00 - Driver Door Shorted Low. ● B25C7-00 - Redundant Driver Door Shorted Low.** ● U0104-00 - Lost Communication With Cruise Control Module (NA Market Only) (In Active or Stored status). ● U0405-00 - Invalid Data Received From Cruise Control Module (NA Market Only) (In Active or Stored status). NOTE: Vehicles setting DTCs U0405-00 and U0104-00 may experience an inability to be cleared.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Transmission and driveline

Trouble codes named

B1810, B25C7, P0072, P0100, P0101, P015B, P015D, P0461, P062B, P0E7C, P0E7D, P0E7E, P0E7F, P2237, P2240, P2243, P2247, P2251, P2254, U0104, U0405, U063C

Vehicles listed
RAM 15002025

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
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1127482026-06-18. Service bulletin. SHIFTER - TRANSMISSION
1127472026-06-18. Service bulletin. SHIFTER - TRANSMISSION
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21-011-25 REV. B2025-12-23. Service bulletin. Flash: Transmission Control Module (TCM) Updates *Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P1B14-00 - Park By Wire Unintended Park Position. ● P1DF3-00 - ECU Not Initialized.** The customer may describe one or more of the following: ● **Secure idle feature not working with Powerpanel On. ● When shifting from Drive to Reverse and vice versa, the transmission detects a mismatch in Neutral as the gear shifter goes from Drive to Reverse through Neutral (D-N-R or R-N-D) and flashes the Neutral indication blinking on the shifter. ● The gear shifter takes too long to get ready when the driver starts the car, and the transmission system couldn't recognize which gear was selected. This gives a warning message "Shift to Park to Obtain Drivability" in the IPC and MIL lamp On. NOTE: For the condition above, the transmission remains in the Park position. ● Shifter can be moved with engine Off and key On while the transmission is in Park and a warning message is displayed in the IPC "Shift to Park to Start". NOTE: For the condition above, the Electric Park Brake (EPB) is activated. ● Auto parking issue.** ● No perceptible change when drive mode is selected. ● Harsh or unstable launches in slippery or off-road conditions. ● Drive mode operating in incorrect drivetrain configurations. ● Bump or jerk felt during Engine Start/Stop (ESS) operation in normal and snow modes. ● Bump during tip-in downshift while in Normal or Sport modes. ● Transmission shifting concerns when vehicle has less than 2,414 km (1,500 mi). ● Driveability concerns and not holding correct gear during downgrade, snow mode and accelerator tip-out maneuvers. **The following software improvements are also included: ● Secure idle fix. ● Shift by wire updates.* This bulletin involves reprogramming the TCM with the latest available software.