Service bulletin 18-101-20 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)
Type	Service bulletin
NHTSA id	10187703
Published by NHTSA	2021-03-01
Manufacturer's number	18-101-20 REV. A
Manufacturer's date	2020-12-11
NHTSA component	POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM); ELECTRICAL SYSTEM

NHTSA's summary

Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience the following:An audible clunk after applying throttle from a coasting condition, predominantly in fifth and sixth gear while driving 48 - 72 kph (30 - 45 mph).

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

Electrical system, Transmission and driveline, Automatic transmission, Transmission control module

Vehicles listed
JEEP CHEROKEE	2021

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

Recalls for the same vehicles and component
21V310000	2021-05-04. POWER TRAIN:AUTOMATIC TRANSMISSION:COOLER/RADIATOR:HOSES AND FITTINGS

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
1807822	2022-12-19. Service bulletin. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find the following DiagnosticTrouble Code (DTC): U0418 - Implausible Data Received From Brake System Control Module. DTC U0418 can be set erroneously due to a low battery (below 10 volts).
1807322	2022-12-19. Service bulletin. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following Diagnostic Trouble Codes (DTCs) have been set: P2097 - Downstream Fuel Trim System 1 Rich. P2099 - Downstream Fuel Trim System 2 Rich.
1812022	2022-09-26. Service bulletin. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more ofthe following DTCs have been set: P1D83 - Implausible Engine Oil Temperature Signal Received. U0418 Implausible Data Received From Brake System Control Module. DTC U0418 can be set erroneously due to a low battery (below 10 volts).Customers may experience the following: An audible clunk after applying throttle from a coasting condition, predominantlyin fifth and sixth gear while driving 48 - 72 kph (30 - 45 mph).
S2125000002	2022-09-26. Service bulletin. Customer complaint includes a Mil-on condition. Upon further investigation, one or more of the following fault codes may be set in the PCM:
18-078-22	2022-06-27. Service bulletin. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more ofthe following DTCs have been set: P0031 - O2 Sensor 1/1 Heater Circuit Low. U0418 - Implausible Data Received From Brake System Control Module. DTC U0418 can be set erroneously due to a low battery (below 10 volts).
S2125000002	2022-05-31. Service bulletin. Customer complaint includes a Mil-on condition. Upon further investigation, one or more of the following fault codes may be set in the PCM:
S2018000012	2020-12-28. Service bulletin. Check engine lamp on. Fault code P0244- TURBOCHARGER/SUPERCHARGER WASTEGATE SOLENOID "A" RANGE/PERFORMANCE is set in the Powertrain Control Module (PCM a.k.a. ECM) after the turbocharger assembly has been replaced.
S2018000012	2020-12-21. Service bulletin. Check engine lamp on. Fault code P0244- TURBOCHARGER/SUPERCHARGER WASTEGATE SOLENOID "A" RANGE/PERFORMANCE is set in the Powertrain Control Module (PCM a.k.a. ECM) after the turbocharger assembly has been replaced.
18-101-20	2020-11-30. Service bulletin. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience the following:An audible clunk after applying throttle from a coasting condition, predominantly in fifth and sixth gear while driving 48 - 72 kph (30 - 45 mph).