When a problem is detected by one of the many sensors linked to the electronic control unit of the Dodge Grand Caravan, the system alerts the driver via a "Service Engine Soon" light. This light is designed to prompt the driver to seek repairs as quickly as possible.
Once the light has been detected, the ECU stores the error code and will often continue to illuminate the Service Engine Soon light, even after repairs are complete. To turn the light off, the ECU must be reset, clearing all error codes and starting from a factory state.
Release and raise the hood. Identify the battery, which is located on your right side when facing the Caravan.
Locate the two cables on top of the battery. The negative cable will be black and has a minus symbol to indicate its polarity.
Loosen the nut on the negative cable using a socket set. Wiggle the cable until it is free and set it aside, making sure it no longer rests against the negative battery terminal. Also ensure the negative cable does not touch the positive cable at any time.
Hold down the horn for a few seconds. This depletes any remaining energy, allowing the ECU to reset more quickly.
Wait at least 15 minutes, then replace the negative terminal, tightening the nut firmly. Close the hood, and start the Caravan. The ECU, along with the Service Engine Soon light, have both been reset.
