# Service bulletin 18\-049\-26

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.

- Type: Service bulletin
- NHTSA id: 11031454
- Published by NHTSA: 2026\-04\-22
- Manufacturer's number: 18\-049\-26
- Manufacturer's date: 2026\-04\-18
- NHTSA component: ENGINE; POWER TRAIN

## NHTSA's summary

Flash: Powertrain Control Module \(PCM\) Updates Customers must experience a Malfunction Indicator Lamp \(MIL\) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes \(DTCs\): ● \*\*P0300 \- Multiple Cylinder Misfire \- In Active or Stored status set during cold start catalyst heating. ● P0301 \- Cylinder 1 Misfire \- In Active or Stored status set during cold start catalyst heating. ● P0302 \- Cylinder 2 Misfire \- In Active or Stored status set during cold start catalyst heating. ● P0303 \- Cylinder 3 Misfire \- In Active or Stored status set during cold start catalyst heating. ● P0304 \- Cylinder 4 Misfire \- In Active or Stored status set during cold start catalyst heating. ● P0305 \- Cylinder 5 Misfire \- In Active or Stored status set during cold start catalyst heating. ● P0306 \- Cylinder 6 Misfire \- In Active or Stored status set during cold start catalyst heating. ● P2066 \- Fuel Level Sensor 2 Performance. ● P152F \- Engine Hood Switch 2 / Engine Hood Switch 1 Correlation.\*\* ● P0401 \- EGR System Performance. ● P00FD \- Battery B State Of Charge Performance. \*\*Customers may also comment on one or more of the following: ● Check engine illuminates when fueling the vehicle while the engine is running. ● Vehicle has a noticeable misfire. ● Vehicle idles rough. ● Engine noise. NOTE: Noise is heard coming from the valvetrain.\*\* In addition, the following software enhancements are available: ● \*\*Update to prevent customers from driving their vehicles while the Electric Park Brake \(EPB\) is engaged. Engine torque will be limited to prevent the Rear Drive Unit from being damaged. NOTE: Previously, the EPB would remain engaged without any torque limit which could lead to the Rear Drive Unit being damaged/broken.\*\* ● Update to enable customers to operate at high state of charge range between 85 to 92%. This bulletin involves reprogramming the PCM with the latest available software.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2026/MC-11031454-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2026/MC-11031454-9999.pdf)

The document is the manufacturer's. This site does not hold it.

## Components

Engine, Transmission and driveline

## Trouble codes named

P00FD, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0401, P152F, P2066

## Vehicles listed

- 2022 JEEP GRAND CHEROKEE
- 2022 JEEP GRAND CHEROKEE L

## Recalls for the same vehicles and component

- [26V413000](/recalls/nhtsa/26V413000.md), 2026-06-30: POWER TRAIN:AUTOMATIC TRANSMISSION:GEAR POSITION INDICATION \(PRNDL\)
- [2023335](/recalls/tc/2023335.md), 2023-06-08: Powertrain
- [23V412000](/recalls/nhtsa/23V412000.md), 2023-06-08: ENGINE
- [2022217](/recalls/tc/2022217.md), 2022-04-28: Engine
- [22V284000](/recalls/nhtsa/22V284000.md), 2022-04-28: ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:GAS RECIRCULATION VALVE \(EGR VALVE\)

## Other bulletins for the same vehicles and component

- [S2621000004](/bulletins/11038329.md), 2026-10-07, Service bulletin: POWER TRAIN. The Customer May Complain About a Popping Noise, Grinding Noise, or an Intermittent No Reverse or Forward Transmission Engagement. The Tech May Find Damaged and/or Worn Transmission Output Shaft Splines \(850RE Transmission Only\)
- [9100363 Rev 3](/bulletins/11036762.md), 2026-09-03, Service bulletin: ENGINE. Turbocharger Kit Please note that many turbo components are serviceable separately and full turbo replacement may not be required. If the turbo is being inspected for: Noise/Rattle: Inspect heat shield fasteners for looseness and check the wastegate actuator/linkage for binding. The actuator kit is serviced separately. Oil Leak: Inspect the turbo oil feed O\-ring area for leaks. O\-ring is serviced separately.
- [113528](/bulletins/11035187.md), 2026-07-23, Service bulletin: POWER TRAIN. SHAFT \- AXLE HALF
- [113529](/bulletins/11035186.md), 2026-07-23, Service bulletin: POWER TRAIN. SHAFT \- AXLE HALF
- [112639](/bulletins/11034912.md), 2026-07-08, Service bulletin: ENGINE. THROTTLE BODY – NONE
- [112640](/bulletins/11034911.md), 2026-07-08, Service bulletin: ENGINE. THROTTLE BODY – NONE
- [112842](/bulletins/11034335.md), 2026-07-02, Service bulletin: ENGINE. BOLT \- HEX FLANGE HEAD
- [21\-041\-26 REV. A](/bulletins/11034324.md), 2026-07-02, Service bulletin: POWER TRAIN. Transmission Auxiliary Oil Pump Failure Customers must experience a Malfunction Indicator Lamp \(MIL\) illumination and the vehicle must SYMPTOM: exhibit/set \*\*one or more the following Diagnostic Troubles Code \(DTCs\): ● U0287\-00 \- Lost Communication With Transmission Fluid Pump Module 1.\*\* ● P0B0D\-00 \- Electric/Auxiliary Transmission Fluid Pump Motor Control Module. Customers may also comment on the following: ● Vehicle is in limp mode. This bulletin involves replacing the transmission oil pump.
- [21\-041\-26](/bulletins/11032847.md), 2026-05-20, Service bulletin: POWER TRAIN. Transmission Auxiliary Oil Pump Failure Customers must experience a Malfunction Indicator Lamp \(MIL\) illumination and the vehicle must exhibit/set the following Diagnostic Trouble Code \(DTC\): ● P0B0D\-00 \- Electric/Auxiliary Transmission Fluid Pump Motor Control Module. Customers may also comment on the following: ● Vehicle is in limp mode This bulletin involves replacing the transmission oil pump.
- [S2623000023](/bulletins/11031337.md), 2026-04-15, Service bulletin: POWER TRAIN; ELECTRICAL SYSTEM. Power Liftgate Inoperative.

JSON: [/v1/bulletins/11031454](/v1/bulletins/11031454)

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