To be certain, you should:
* Consult your owner's manual: This is the best place to start. The manual will have a diagram showing the location of all major components, including the ECM.
* Check online resources: Websites like Haynes or Chilton provide repair manuals with diagrams for your specific year and model.
* Look for a large, rectangular black box: The ECM is usually a fairly large, black plastic box with numerous connectors. It might have labels or markings indicating its purpose.
Remember to disconnect the negative battery terminal before working near any electrical components in your vehicle.