Where is the eccs relay located on a 1999 Nissan Frontier?

On a 1999 Nissan Frontier, the ECCS (Engine Control Computer System) relay is typically located in the fuse box under the hood. This fuse box is situated near the battery, on the driver's side of the engine compartment. You can identify the ECCS relay by looking at the diagram on the fuse box cover, which labels the various relays and fuses. Always consult the vehicle's manual for specific locations and diagrams.