Where is the ecm for 1999 suburban?

The Engine Control Module (ECM) for a 1999 Chevrolet Suburban is typically located in the engine compartment, mounted on the passenger side near the firewall. It may be positioned near the battery or the fender well. To access it, you may need to remove some covers or components, depending on the specific configuration of the vehicle. Always refer to the vehicle's service manual for precise instructions.