# Service bulletin 18\-058\-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: 11033868
- Published by NHTSA: 2026\-06\-16
- Manufacturer's number: 18\-058\-26
- Manufacturer's date: 2026\-06\-04
- NHTSA component: POWER TRAIN

## NHTSA's summary

Flash: Powertrain Control Module \(PCM\) Updates Customers must experience a Malfunction Indicator Lamp \(MIL\) illumination and the vehicle must exhibit/set one of the following Diagnostic Trouble Codes \(DTCs\): ● P1CEA \- Boost Side Evap Purge System Performance. ● P0300\-00 \- Random/Multiple Cylinder Misfire Detected ● P0301\-00 \- Cylinder 1 Misfire ● P0302\-00 \- Cylinder 2 Misfire ● P0303\-00 \- Cylinder 3 Misfire ● P0304\-00 \- Cylinder 4 Misfire Customers may also experience one or more of the following: ● Engine RPM fluctuations at low vehicle speeds after extended idling. ● An ignition\-off draw or battery drain condition. ● Sluggish engine performance and misfires. ● Engine knocking when the accelerator is pressed hard or quickly This bulletin involves inspecting and possibly reprogramming the PCM and Transmission Control Module \(TCM\) with the latest available software.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2026/MC-11033868-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2026/MC-11033868-9999.pdf)

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

## Components

Transmission and driveline

## Trouble codes named

P0300, P0301, P0302, P0303, P0304, P1CEA

## Vehicles listed

- 2026 JEEP GRAND CHEROKEE
- 2026 JEEP GRAND CHEROKEE L

## 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 \(850RE Transmission Only\)
- [08\-289\-26 REV. A](/bulletins/11035971.md), 2026-08-06, Service bulletin: POWER TRAIN. Transmission Control Module \(TCM\) Diagnostic N/A \- This bulletin was released in error. SYMPTOM:
- [08\-289\-26](/bulletins/11035313.md), 2026-07-29, Service bulletin: ELECTRICAL SYSTEM; POWER TRAIN. Transmission Control Module \(TCM\) Diagnostic Customers may experience a Malfunction Indicator Lamp \(MIL\) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following DTCs: ● P2797\-00 \- Auxiliary Transmission Fluid Pump Performance ● P1625\-00 \- Park Pawl System Failure NOTE: Park system still functions, no impact to park engagement. NOTE: Vehicle will not experience unintended movement. Customers may also experience one or more of the following: ● Vehicle no start due to battery discharge. ● 'Start/stop inop' message. ● 'Service Transmission' message on in Instrument Panel Cluster \(IPC\).
- [21\-053\-26](/bulletins/11034906.md), 2026-07-08, Service bulletin: POWER TRAIN. Service Transmission Message Customers must experience a Malfunction Indicator Lamp \(MIL\) illumination and the vehicle must SYMPTOM: exhibit/set the following Diagnostic Trouble Code \(DTC\): ● P2797\-00 \- Auxiliary Transmission Fluid Pump Performance. Customers may also comment on the following: ● Engine Stop\-Start \(ESS\) does not operate. ● "Service Transmission" message displayed in the Instrument Panel Cluster \(IPC\). This bulletin involves inspecting and possibly replacing the transmission oil pump motor.
- [21\-049\-26](/bulletins/11033870.md), 2026-06-16, Service bulletin: POWER TRAIN. Flash: Transmission Control Module \(TCM\) Updates Customers may experience one or more of the following: ● Intermittently during low‑speed parking maneuvers when the driver moves from Drive \(D\) to Reverse \(R\) at the exact moment the Engine Stop/Start \(ESS\) system shuts the engine off. ● When the timing aligns, the engine will not automatically restart, and the Instrument Panel Cluster \(IPC\) displays a shift to park to start reated message. ● NOTE: The behavior results from safety logic that prevents the PCM from restarting the engine while the transmission is in an engaged gear. NOTE: No Diagnostic Trouble Codes \(DTCs\) or Malfunction Indicator Lamp \(MIL\) are set because the system is functioning as designed. NOTE: This may appear as an ESS stall, but it is actually a controlled inhibit, not a malfunction. NOTE: The condition is difficult to reproduce due to the timing window required. This bulletin involves inspecting and possibly reprogramming the PCM and Transmission Control Module \(TCM\) with the latest available software.
- [S2621000003 REV.A](/bulletins/11030138.md), 2026-03-18, Service bulletin: POWER TRAIN. The vehicle will exhibit a service transmission/check engine warning indicator for the following transmission models: 845RE, 8HP45, 850RE, 8HP50, 8HP70, 8HP75, 8HP75\-PHEV, 8HP75\-LCV, 8HP90, 8HP95. Transmissions may exhibit the following diagnostic codes: P07E4, P1DB2, P0716, P1B14, P0733, P1D90, P1DB7, P1B13.
- [S2621000003](/bulletins/11029770.md), 2026-03-05, Service bulletin: POWER TRAIN. Service transmission/check engine warning indicator for the 850RE, 8HP50, 8HP70, 8HP75, 8HP75\-PHEV transmissions that have fault codes P07E4, P1DB2, P0716, P1B14, P0733, P1D90, P1DB7, P1B13.
- [S2521000004 REV.B](/bulletins/11027739.md), 2026-01-21, Service bulletin: STEERING; SUSPENSION; POWER TRAIN. The customer is experiencing a clicking or pop noise from the steering knuckle and bearing area during turns while driving.
- [109011](/bulletins/11026815.md), 2025-12-23, Service bulletin: POWER TRAIN. VALVE BODY \& CONTROL UNIT – TRANSMISSION
- [S2521000005](/bulletins/11026809.md), 2025-12-23, Service bulletin: SERVICE BRAKES; POWER TRAIN. The customer states the ABS and Traction Control warning comes on. Vehicle sets wheel speed BSCM/ABS fault codes.

JSON: [/v1/bulletins/11033868](/v1/bulletins/11033868)

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