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2018-2019 Charger, Challenger & 300 3.6L ECM: Your Guide to Programming, Failure Symptoms, and Replacement

This guide covers the critical programming requirements and common failure symptoms for the 3.6L V6 engine control module in your Dodge or Chrysler.

5 minutes to read 2018-2019 Chrysler 300 2018-2019 Dodge Charger 2018-2019 Dodge Challenger
Difficulty
2/5
Est. Time
0.75 hrs
DIY Doable?
✅ Yes
Shop Labor
$125 - $250
Used OEM Price
$50 - $150
🚫 Do not drive — No, it is not safe to drive. A failing ECM can cause the engine to stall unexpectedly in traffic, creating a significant safety hazard.
Key Takeaways
  • A replacement ECM for these vehicles MUST be programmed to your car's VIN to disable the anti-theft system and allow the car to start.
  • The easiest option for most people is to buy a remanufactured, pre-programmed 'plug-and-play' module online.
  • Ensure the replacement ECM is for a 3.6L engine; modules from V8 models are not compatible.
  • Common failure symptoms include a no-start condition, random stalling, poor performance, and a check engine light with multiple unrelated codes.
The Engine Control Module (ECM), also called the Powertrain Control Module (PCM), is the central computer or 'brain' of your vehicle's engine. It receives data from sensors all over the engine and drivetrain to make millions of calculations per second. Based on this data, it precisely controls the fuel injectors, ignition timing, and variable valve timing to ensure the engine runs efficiently, makes good power, and meets emissions standards. It is a critical component that is essential for the vehicle to start and run correctly.

Symptoms of a Failing ECM

A failing Engine Control Module in a 2018-2019 Dodge Charger, Dodge Challenger, or Chrysler 300 can cause a wide range of confusing and intermittent issues. Because the ECM controls so many different functions, its failure can sometimes be misdiagnosed as a bad sensor or another component.

  • Check Engine Light: This is often the first and most obvious sign. The light may be on constantly, or it may come and go.
  • Engine Stalling or Misfiring: The engine may stall unexpectedly while driving or at idle. You might also notice a rough idle, stuttering, or hesitation during acceleration.
  • No-Start Condition: The engine may crank but refuse to start. This happens because the ECM is not properly commanding the fuel and spark systems.
  • Poor Performance and Fuel Economy: A sudden, noticeable drop in gas mileage or a feeling that the car is sluggish and lacks power can point to an ECM issue.
  • Erratic Transmission Shifting: On automatic transmission models, the ECM communicates with the transmission controller. A faulty ECM can cause harsh shifting, delayed shifts, or getting stuck in one gear (limp mode).
  • 🎬 See how to fix no-crank and communication issues.
  • Multiple Unrelated Trouble Codes: A classic sign of ECM failure is when a scan tool reveals a long list of error codes for various different sensors and systems. This often indicates the central computer is the problem, not every individual sensor.
  • 🎬 Watch: Everything you need to know about ECM replacement.

Common Diagnostic Trouble Codes (DTCs)

While many codes can be triggered by a failing ECM, codes specifically related to the module's internal circuitry often start with P0600 through P0605. Seeing one of these is a strong indicator that the ECM itself is the problem.

Known Issues, Recalls, and Technical Service Bulletins (TSBs)

In May 2018, FCA issued a major safety recall (NHTSA Campaign Number 18V332000, also known as FCA recall U68) for a software issue that could prevent the cruise control from being canceled. This recall required dealers to perform a software update (a 'flash') on the Powertrain Control Module.

Important: According to the official NHTSA documentation, this specific recall only applied to 2018 Dodge Charger and Challenger models equipped with the 6.4L engine, not the 3.6L V6 that this guide covers. However, it highlights the importance of ensuring your vehicle's software is up to date, as dealers often apply other available updates during a service visit.

Buying a Used Engine Control Module (ECM)

For owners of a 2018-2019 Dodge Charger, Challenger, or Chrysler 300, replacing a faulty ECM is not as simple as swapping the part. Due to the integrated anti-theft system, programming is a mandatory and critical step.

The #1 Rule: Programming is NOT Optional

A replacement ECM, whether it is brand new, used, or remanufactured, must be programmed to your vehicle’s unique Vehicle Identification Number (VIN). This process electronically pairs the new module to the other computers in your car, including the ignition and anti-theft system (also known as the Sentry Key Immobilizer Module, or SKIM).

Warning: If you install a used ECM without programming it, the vehicle will not start. The anti-theft system will prevent the engine from running, as it does not recognize the new 'brain'.

Compatibility: Match the Part Number and Engine

You must use an ECM designed for the 3.6L V6 engine. Modules from 5.7L Hemi or 6.4L Scat Pack models are not compatible. The primary OEM part number for this application is Mopar 68330904AA. While other part numbers may exist due to software updates or minor hardware revisions, starting with this number is your best bet. Always verify compatibility with the seller before purchasing.

Who Can Program a Replacement ECM?

You have several options for getting a replacement module programmed:

  • Pre-Programmed Modules: Many online vendors sell used or remanufactured ECMs that are 'plug-and-play'. You provide them with your car's VIN when you order, and they program the module before shipping it to you. This is often the easiest and most cost-effective option for DIYers.
  • Mail-In Programming Services: You can purchase a used ECM from any source and mail it to a specialized service. For a fee, they will program it with your VIN and ship it back to you.
  • Dealership: A Chrysler, Dodge, or Jeep dealer can always program a new or used module, but this is typically the most expensive route.
  • Independent Auto Shops & Locksmiths: Many modern repair shops and some specialized automotive locksmiths have the professional scan tools (like a J2534 pass-through device) and software subscriptions needed to perform this programming.

ECM Replacement Overview

The physical replacement of the ECM is straightforward and can be performed by a DIY mechanic with basic tools.

  1. Location: The ECM is located in the engine bay on the passenger's side, underneath the plastic cowl panel near the windshield and cabin air filter.
  2. Disconnect Battery: Always disconnect the negative battery terminal before working on any electronic components.
  3. Access the Module: Remove the plastic pop-rivets holding the cowl cover in place and remove the cover.
  4. Disconnect Connectors: The ECM has two large electrical connectors with red locking tabs and gray levers. Slide the red tabs, then rotate the levers to disengage the connectors.
  5. Remove Module: Unbolt the ECM from its mounting bracket. It is typically held 🎬 Watch this walkthrough on how to remove the module. by a few 10mm or 13mm bolts.
  6. Installation: Installation is the reverse of removal. Ensure the connectors are seated fully and the locking levers are fully engaged before reconnecting the battery.

Cost Comparison for a Replacement ECM

Part TypeEstimated CostNotes
New OEM$650 - $1,010Part only. Does not include dealer programming labor.
Remanufactured (Pre-Programmed)$200 - $400Often sold as 'plug-and-play'. A good balance of value and convenience.
Used OEM (Unprogrammed)$50 - $150Cheapest initial cost, but requires separate programming.
Shop Labor (Programming Only)$125 - $250Cost for a dealer or independent shop to program a module you provide.

Frequently Asked Questions (FAQ)

Can I just swap in a used ECM and start the car?

No. The vehicle's anti-theft system is linked to the ECM. A replacement module must be programmed to your car's VIN to be recognized by the other systems, otherwise the car will not start.

What's the difference between 'flashing' and 'programming'?

While often used interchangeably, 'flashing' typically refers to updating the software on an existing module (like for a recall). 'Programming' usually refers to the initial setup of a new or used module, which includes writing the vehicle's VIN and security information to it for the first time.

Can I use an ECM from a 5.7L Hemi in my 3.6L V6?

No. The ECM is specific to the engine and its components. You must use a module from another vehicle with a 3.6L engine.

Do I need to do a 'key relearn' procedure after installing a pre-programmed ECM?

In most cases, if the ECM is properly programmed to your VIN by the seller, no additional key relearn is necessary. The module is programmed to work with your existing keys. However, some sellers may provide specific instructions if a simple key cycle procedure is needed.

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FIXED WITHOUT A $1,000+ SCAN TOOL! DODGE CHALLENGER NO CRANK / NO COMM WITH TCM!
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Chrysler 300 ECM Replacement - Everything You Need To Know
Chrysler 300 ECM Replacement - Everything You Need To Know

Technical Specifications

OEM Part Numbers: 68330904AA P68330904AA 68395671 68395672 68395683 68395684 68395685 68395687

Module controls engine, fuel, spark, and emissions systems. Integrates with vehicle immobilizer (anti-theft).

Wrenchy
Article researched & written by
Go-Parts' AI research assistant. Every article is backed by live web research, verified OEM data, and real technician knowledge — so you get accurate, up-to-date information you can trust.
Meet Wrenchy → Updated Jul 21, 2026

The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.

Year Coverage
This article covers the Engine Control Module (ECM) for:
  • Dodge Charger: 20182019
  • Chrysler 300: 20182019
  • Dodge Challenger: 20182019
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