2008-2010 Charger, 300, Challenger & Magnum ECM: Why VIN Programming is Not Optional

Symptoms of a Failing ECM

A faulty Engine Control Module can cause a wide range of problems, from noticeable performance issues to your car not starting at all. Because the ECM controls so many functions, symptoms can sometimes be mistaken for other issues. However, if you experience several of the following, the ECM is a likely culprit.

• Check Engine Light: A constant check engine light is a common sign. The light may stay on even after clearing codes, or you may see codes related to various sensors or circuits all at once.
• Engine Stalling or Misfiring: The engine may stall unexpectedly, either at idle or while driving. You might also experience a rough idle, engine stumbling, or misfires as the ECM fails to correctly manage fuel and spark.
• Car Won't Start: This can manifest in two ways. The engine may crank but never start, or it may start for a second and then immediately shut off. The start-and-stall issue is a classic sign of an anti-theft system problem, which is directly tied to the ECM.
• Poor Performance and Fuel Economy: You may notice a sudden drop in gas mileage or a significant loss of power and acceleration. The vehicle might feel sluggish or hesitate when you press the gas pedal.
• Erratic Transmission Shifting: For vehicles covered by this module, the ECM plays a role in transmission behavior. A failing module can cause harsh, delayed, or unpredictable shifting with the 4-speed automatic transmission.

Common Diagnostic Trouble Codes (DTCs)

A failing ECM often won't set a code for itself (e.g., "P0601: Internal Control Module Memory Check Sum Error"). Instead, you're more likely to see codes for the systems it controls. You might find multiple, seemingly unrelated codes for injector circuits, sensor reference voltage, or communication errors. If you see a code like P0633 (SKIM Key Not Programmed), it points directly to a programming issue between the ECM and the anti-theft system. Additionally, a technical service bulletin (TSB) exists for some models that can erroneously throw a P2181 (Cooling System Performance) code, which is resolved by a software update to the ECM.

Buying a Used Engine Control Module: What You Must Know

Replacing the ECM in these vehicles isn't as simple as swapping the part. Due to strict compatibility and anti-theft requirements, you must follow specific steps to ensure the replacement module will work.

1. Verify Part Number and Engine/Drivetrain Compatibility

This is the first and most critical step. This specific ECM was used in several vehicles but only with specific engines and drivetrains.

• Fits vehicles with the 2.7L V6 engine.
• Fits vehicles with the 3.5L V6 engine, BUT ONLY if the vehicle is Rear-Wheel Drive (RWD) and has a 4-speed automatic transmission.

Do not attempt to use an ECM from a 5.7L Hemi or a 3.5L High-Output All-Wheel Drive (AWD) model. The programming and hardware are different and will not work. Always match the OEM part number from your original module to the replacement. Known compatible part numbers include 05187010AD, 5150246AD, 5150246AE, 51870110AD, 5187021AD, and 68054120AD.

2. The #1 Rule: Programming is NOT Optional

A used ECM will not work if you simply install it. Every ECM is electronically tied to the original vehicle's Vehicle Identification Number (VIN). It is also linked to the Sentry Key Immobilizer Module (SKIM), which reads the chip in your key.

If you install an unprogrammed ECM, one of two things will happen:

1. The car will not crank at all.
2. The car will start, run for 2-3 seconds, and then immediately shut off. This is the SKIM system doing its job, preventing theft by shutting down the engine when it doesn't recognize the ECM.

3. How to Get a Replacement ECM Programmed

You have three main options for programming a replacement ECM:

• "Plug and Play" Pre-Programmed Module: This is the most popular option for DIYers. Many online retailers sell used or remanufactured ECMs that are pre-programmed before they are shipped. You provide the seller with your car's VIN during checkout, and they flash the module so it's ready for installation upon arrival. This makes the replacement a true "plug and play" process with no special tools needed.
• Dealership: A Chrysler, Dodge, or Jeep dealership can program a new or used ECM to your vehicle using their proprietary WiTech diagnostic tool. This is a guaranteed but often most expensive option.
• Independent Repair Shop: Some independent shops have advanced, professional-grade scan tools (like high-end Autel or Snap-on models) and the J2534 pass-through equipment required to perform factory-level programming. You will need to call ahead to confirm they have this capability for Chrysler vehicles.

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

While there are no major recalls for widespread failure of the ECM itself, these vehicles have been subject to other recalls and TSBs you should be aware of.

• Airbag Recalls: Most of these vehicles were included in the massive Takata airbag recalls. The driver and/or passenger side airbag inflators could rupture, causing serious injury. This is a critical safety repair that should be performed by a dealer.
• Keyless Go Recall: Some 2008-2009 Dodge Challenger models had a recall (NHTSA #08V481000) where the engine could be turned off with the transmission not in Park, creating a rollaway risk.
• TSB 18-021-13 (2009 Challenger): This TSB addresses a condition where the vehicle may have reduced power immediately after a cold start if accelerating at wide-open throttle. The fix is to reprogram (flash) the PCM with updated software.

ECM Location and Replacement Overview

Physically replacing the ECM is a simple process that can be done with basic tools.

Location: The ECM is located in the engine compartment on the passenger side, near the firewall and shock tower. It is a silver metal box with three large electrical connectors.

Tools Needed: 13mm socket and ratchet.

1. Disconnect the battery. This is a crucial safety step. The battery is located in the trunk. Disconnect the negative terminal.
2. Locate the ECM. Find the silver module on the passenger side of the engine bay.
3. Unplug the connectors. There are three large, color-coded connectors. Each has a red locking tab. Slide the red tab to the side, then press the release button and pull the connector lever to disengage it. The connectors are color-coded to prevent mixing them up.
4. Remove the mounting bolt. A single 13mm bolt holds the ECM bracket in place. Remove this bolt.
5. Remove the ECM. The module can now be lifted out of the vehicle.
6. Installation is the reverse of removal. If you are using a pre-programmed module, the car should start and run normally after reconnecting the battery.

Cost Breakdown

The cost to get your vehicle back on the road can vary significantly based on the path you choose.

Frequently Asked Questions (FAQ)