Service bulletin 18-014-20 REV. B

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	10177533
Published by NHTSA	2020-07-27
Manufacturer's number	18-014-20 REV. B
Manufacturer's date	2020-06-19
NHTSA component	ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING; POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM)

NHTSA's 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 that one or more of the following DTCs have been set:P2C90 - Crankcase Ventilation System - Hose "A" Disconnected(APAC, EMEA and LATAM Only). P04FC - Crankcase Ventilation System Performance(APAC, EMEA and LATAM Only). P2453 - Particulate Filter Pressure Sensor "A" Circuit Range/Performance(APAC and EMEA only equipped with Gas Particulate Filter (GPF). P245F - Particulate Filter Pressure Sensor "B" Circuit Range/Performance(APAC and EMEA only equipped with Gas Particulate Filter (GPF). P0456 - EVAP System Small Leak. If DTC P0456 is present use wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. P0171 - Fuel System 1/1 Lean(LATAM Only). P0172 - Fuel System 1/1 Rich(LATAM Only). P0128 - Thermostat Rationality(Sales Codes NA1 with NBQ or NB6 Only - APAC and EMEA Only). P050B - Cold Start Ignition Timing Performance(Sales Codes NA1 with NBQ or NB6 Only - APAC and EMEA Only). Customers may comment on one or more of the following:Excessive fan noise when the A/C is on MAX output. Rough idle at engine start up in colder ambient temperatures. Software enhancements also included in this update:Electric Vacuum Pump (EVP) update. Fan noise reduction. Low Speed Pre Ignition (LSPI) update.

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, Engine, Transmission and driveline, Automatic transmission, Transmission control module

Trouble codes named

P0128, P0171, P0172, P0456, P04FC, P050B, P2453, P245F, P2C90

Vehicles listed
JEEP WRANGLER	2018

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

Recalls for the same vehicles and component
18V280000	2018-05-01. POWER TRAIN:AUTOMATIC TRANSMISSION

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
S2325000006	2023-08-21. Service bulletin. Customer complaint may include a MIL-on or check engine lamp on condition.
S1808000152	2023-04-17. Service bulletin. CEL (Check Engine Lamp) Illuminates, Recent PCM Replace or Flash Update Performed, Diagnostic Trouble Codes (DTCs) P057B Brake Pedal Position Sensor Circuit Performance, P1572 Brake Pedal Stuck, C0042-54 Brake Pedal Missing Calibration
S2207000002	2023-01-09. Service bulletin. Coolant leak
1801420	2022-10-17. 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 that one or more of the following DTCs have been set:P2C90 - Crankcase Ventilation System - Hose "A" Disconnected(APAC, EMEA and LATAM Only). P04FC - Crankcase Ventilation System Performance(APAC, EMEA and LATAM Only). P2453 - Particulate Filter Pressure Sensor "A" Circuit Range/Performance(APAC and EMEA only equipped with Gas Particulate Filter (GPF). P245F - Particulate Filter Pressure Sensor "B" Circuit Range/Performance(APAC and EMEA only equipped with Gas Particulate Filter (GPF). P0456 - EVAP System Small Leak. If DTC P0456 is present use wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. P0171 - Fuel System 1/1 Lean(LATAM Only). P0172 - Fuel System 1/1 Rich(LATAM Only). P0128 - Thermostat Rationality(Sales Codes NA1 with NBQ or NB6 Only - APAC and EMEA Only). P050B - Cold Start Ignition Timing Performance(Sales Codes NA1 with NBQ or NB6 Only - APAC and EMEA Only). Customers may comment on one or more of the following:Excessive fan noise when the A/C is on MAX output. Rough idle at engine start up in colder ambient temperatures. Software enhancements also included in this update:Electric Vacuum Pump (EVP) update. Fan noise reduction. Low Speed Pre Ignition (LSPI) update.
1801820	2022-09-26. Service bulletin. Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. The customer may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more ofthe following DTCs: P04FC - Crankcase Ventilation System Performance. P0456 EVAP System Small Leak.If DTC P0456 is present use the wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. P061A - Level 2 Torque Performance. P0507 - Idle Speed Performance Higher Than Expected. Customers may also describe the following condition:Excessive fan noise when the A/C is on MAX output. Other enhancements included in this update: Electric vacuum pump (EVP) update. Fan noise reduction.
1803621	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 f Customers may comment on one or more of the following: Excessive fan noise when the A/C is on MAX output. Rough idle at engine start up in colder ambient temperatures. The following software enhancements are also included in this update : Electric Vacuum Pump (EVP) update. Fan noise reduction. Low Speed Pre Ignition (LSPI) update.
S1918000008 Rev.	2022-07-18. Service bulletin. Customer?s complaint may include a MIL-on with one or more of the following DTCs (Active, Pending, or Stored) in the PCM: P0133, P0137, P0171, P0300, P2096. The root cause could be due to oil leaking from Bank 1 valve cover seal on to the 1/2 (Bank 1 downstream) O2 sensor. This can adversely affect the 1/2 O2 sensor signal reading and lead to listed DTCs. Before performing normal diagnostic routines for the above codes, check for the condition listed above.
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.
18-014-20 REV. A	2020-05-18. 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 that one or more of the following DTCs have been set:P0456 - EVAP System Small Leak.If DTC P0456 is present use wiTECH Small Leak Verification Test (SLVT) to determine if a leak is present in the system. P0171 - Fuel System 1/1 Lean(LATAM Only). P0172 - Fuel System 1/1 Rich(LATAM Only). P0128 - Thermostat Rationality(APAC&EMEA with Sales Codes NA1 with NBQ or NB6 Only). P050B - Cold Start Ignition Timing Performance(APAC&EMEA with Sales Codes NA1 with NBQ or NB6 Only). Customers may experience:Excessive fan noise when the A/C is on MAX output. Rough idle at engine start up in colder ambient emperatures. Software enhancements include:Electric Vacuum Pump (EVP) update. Fan noise reduction. Low Speed Pre Ignition (LSPI) update.