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Service bulletin 18-001-24 REV. C

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 id11007658
Published by NHTSA2024-09-10
Manufacturer's number18-001-24 REV. C
Manufacturer's date2024-09-07
NHTSA componentPOWER TRAIN; FUEL/PROPULSION SYSTEM
Manufacturer's systemPowertrain Control Module

NHTSA's summary

"Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician must find one or more of the following Diagnostic Trouble Codes (DTCs) have been set: ● **P0629 - Fuel Pump Control Circuit High. ● P0171 - Fuel system Lean. ● P0087 - Fuel Rail Pressure Too Low - Bank 1.** ● P16F0-00 - SPI Comm Hardware Fault. Customers may also experience one or more of the following: ● **The rear half shafts are damaged due to pressing the accelerator in drive with the Electric Parking Brake (EPB) applied. ● The Oxygen Sensor (02) can give wrong values when entering EV mode, triggering a false MIL. ● The Instrument Cluster Panel (ICP) unable to calculate the instantaneous fuel economy under heavy acceleration. ● Variable Speed Fuel Pump inoperative after refueling (no start).** ● Intelligent sign recognition is not working properly causing degradation in active speed limiting functionality (IAP Only). ● Shifts rough occasionally when coming down to a stop. ● Shifts rough occasionally when accelerating. ● Shifts rough when transitioning from EV to Hybrid operation on low SoC. ● Shifts rough when engines starts. ● On part throttle accelerations with little to no battery available the transition from battery power to engine on is harsh and abrupt. ● The engine oil life on dashboard drops down too fast when the engine oil dilution reaches high level without the ability to recover. This bulletin involves reprogramming the PCM, Transmission Control Module (TCM) and the Auxiliary Hybrid Control Processor (AHCP) also known as Power Inverter Module (PIM), with the latest available software."

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

Fuel system, Transmission and driveline

Trouble codes named

P0087, P0171, P0629, P16F0

Vehicles listed
JEEP GRAND CHEROKEE2023

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

Recalls for the same vehicles and component
26V4130002026-06-30. POWER TRAIN:AUTOMATIC TRANSMISSION:GEAR POSITION INDICATION (PRNDL)

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

Other bulletins for the same vehicles and component
S26210000042026-10-07. Service bulletin. 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)
1135282026-07-23. Service bulletin. SHAFT - AXLE HALF
1135292026-07-23. Service bulletin. SHAFT - AXLE HALF
9100833 REV12026-07-18. Service bulletin. Fuel Delivery Module Before replacing the fuel module for DTCs P0461 and P062A and other not start, long crank, fuel gauge accuracy and drivability issues, the technician should disconnect the electrical connector at the pump and perform a visual inspection of the connector for and bent, spread, or pushed out terminals. Repair any issues found. Reconnect the plug and perform a push pull push to ensure the connector is fully installed. Then perform 3 keys cycles and listen to hear if the fuel pump is operational. If the fuel pump is heard that indicates that everything is operating correctly. If the pump is heard replacement is not necessary, any replacement will function in the same way.
91008332026-07-02. Service bulletin. Fuel Delivery Module Before replacing the fuel module for DTCs P0461 and P062A and other not start, long crank, fuel gauge accuracy and drivability issues, the technician should disconnect the electrical connector at the pump and perform a visual inspection of the connector for and bent, spread, or pushed out terminals. Repair any issues found. Reconnect the plug and perform a push pull push to ensure the connector is fully installed. Then perform 3 keys cycles and listen to hear if the fuel pump is operational. If the fuel pump is heard that indicates that everything is operating correctly. If the pump is heard replacement is not necessary, any replacement will function in the same way.
21-041-26 REV. A2026-07-02. Service bulletin. 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.
21-041-262026-05-20. Service bulletin. 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.
18-051-262026-04-22. Service bulletin. 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.** ● C053D - Brake Pressure Sensor 1 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 enhancement is 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.** This bulletin involves reprogramming the PCM with the latest available software.
S2621000003 REV.A2026-03-18. Service bulletin. 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.
S26210000032026-03-05. Service bulletin. 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.