Jeep Wrangler 2021 — technical service bulletin
Bulletin 1804122 · NHTSA communication 10229157 · issued Mar 19, 2022
Technical service bulletin
communication type
Electrical System
component
2021
model years
1
vehicle entries
Official summary
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 DTC: P0300 - Multiple Cylinder Misfire. In addition, customers may experience the following concern: Spark knock/detonation sound from the engine at idle.
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.