5677664 | Genuine Cummins® Engine Controller Module 2023-2024 Ram

An Engine Control Module (ECM) 5677664 - also called an Engine Control Unit (ECU)—is a computer in a vehicle that controls and manages how the engine operates. It’s one of the most important electronic components in modern cars.

General Specifications

Fitment

Fitment can vary by engine build and options. Match the part number on the part you are replacing, or contact us with your vehicle details before ordering.

Purpose & Function

The ECM constantly monitors sensors throughout the engine and makes adjustments to keep everything running efficiently. Its main jobs include:

1. Controlling fuel injection
   It decides how much fuel to send to the engine based on conditions like throttle position, air temperature, and engine load.

2. Controlling ignition timing
   It determines when the spark plugs should fire for the best power and fuel efficiency.

3. Managing air–fuel mixture
   It ensures the engine gets the right amount of air and fuel for smooth operation.

4. Monitoring emissions
   It adjusts the engine to reduce pollution and meet emission standards.

5. Running diagnostic checks
   If something goes wrong, the ECM stores trouble codes and turns on the Check Engine Light.

6. Working with other systems
   It communicates with the transmission control module, ABS, traction control, etc.

Signs of Engine Controller Module

1. Check Engine Light Stays On or Comes Back Repeatedly

If the ECM is malfunctioning, it may trigger random or incorrect trouble codes—even after repairs.

2. Engine Misfires or Runs Rough

A failing ECM may send wrong signals to the injectors or ignition system, causing misfires, shaking, or rough idling.

3. Poor Fuel Economy

Because the ECM controls the air–fuel mixture, a bad module can make the engine burn more fuel than normal.

4. Difficulty Starting or No Start

If the ECM fails completely, the engine may crank but not start—because fuel injection and spark timing are not being managed.

5. Engine Stalling or Cutting Out

Intermittent ECM issues can cause the engine to randomly stall while driving or idling.

6. Loss of Power or Limp Mode

The ECM may restrict engine performance to protect the vehicle, causing sluggish acceleration.

7. Transmission Shifting Problems

In many cars, the ECM communicates with the transmission control module. A bad ECM can cause hard shifts or wrong gear timing.

8. Incorrect or Strange Sensor Readings

If the ECM can’t process sensor data correctly, you might see:

• incorrect temperature readings

• fluctuating RPM

• wrong fuel trim values

About Cummins

Cummins is a leading American manufacturer of diesel and natural gas engines, as well as power generation systems and emissions solutions. Founded in 1919 and headquartered in Columbus, Indiana, Cummins is known globally for its durable, high-performance engines used in trucks, buses, construction equipment, agriculture, and power systems.

The brand is widely respected for its innovation in clean diesel technology, including aftertreatment systems, turbochargers, and advanced electronics that help reduce emissions while maximizing engine efficiency and reliability.