The key functions of the ECM are to regulate the timing of the ignition, the amount of fuel delivered to the engine and other components to meet the precise parameters that your vehicle’s engine requires to run smoothly. This is accomplished by the module constantly reading values obtained by various performance maps and using signals generated by other devices monitoring the engine.
There are some common symptoms your vehicle will exhibit when things are out of sync. Typically, there will also be one or more Diagnostic Trouble Code (DTC) once the vehicle has been scanned.
- No start, hard start, slow cold start, engine stalls, rough idle, high idle, misfire, loss of power. Possible issue: No signal to ignition coil, no pulse to injector, communication issue with ECM/ECU.
- Transmission shifting problems or harsh/erratic transmission shifts. Transmission speed sensors are used to calculate the actual gear ratio of the transmission while in use. Possible issue: Bad or failing transmission speed sensor, or shift solenoid IC chip.
- Vehicle in fail-safe mode (loss of power). This is a design feature that inherently responds to failure in a way that will cause no or minimal harm to other vehicle equipment by altering transmission shift, engine RPM, or engine load conditions. Possible issue: A problem with the logic of a vehicle’s computer when the signal value sent by a sensor to the control module is not within a pre-programmed range specified by the manufacturer.
- DTC error codes for ECM/ECU.
What is a Diagnostic Trouble Code?
Diagnostic Trouble Codes (or fault codes) are codes that are stored by the on-board computer diagnostic system. These are stored in response to a problem found in the vehicle by the system. These codes are stored when a sensor in the vehicle reports a reading that is outside the normal or accepted range (for example, if the fuel mixture is too rich).
Trouble Codes Are Subdivided Into Four Basic Categories:
- Powertrain (“P”) codes (engine, transmission and emissions systems)
- Body (“B”) codes (Climate control system, lighting, airbags, etc.)
- Chassis (“C”) codes (antilock brake system, electronic suspension and steering systems)
- Network Communications (“U”) codes (controller area network wiring bus and modules)
Take action and avoid possible further vehicle damage by seeking help from ModuleExperts if your vehicle is exhibiting any of these symptoms or you’ve had it scanned and have Diagnostic Trouble Codes.
ModuleExperts brings more than 100 years of combined experience in module diagnostics, repairs and remanufactured replacements for all types of control modules. Our A+ BBB rating proves our commitment to first-class customer service and satisfaction. Contact us today to learn more about how we can help service your control module needs.