Instead, various relays within the underhood fuse box and potentially the cab fuse box control circuits *related* to the PCM's operation. These might include relays for the fuel pump, ignition system, or other components the PCM manages.
To find the relevant relays:
1. Consult your owner's manual: This is your best resource. Look for diagrams of the fuse and relay boxes, and locate relays associated with fuel injection, ignition, or the PCM itself (sometimes listed as the engine control module or ECM).
2. Check the underhood fuse box: This is the most likely location for relays controlling major powertrain systems. The box usually has a cover with a diagram showing the location of each fuse and relay.
3. Check the cab fuse box (if equipped): Some less power-intensive circuits might be controlled by relays here.
4. Use a multimeter: If you're comfortable with basic electrical testing, you can trace wires from the PCM to identify which relays control related circuits. However, this should only be done with the ignition OFF to avoid electrical shock.
Without knowing your specific engine (e.g., 2.5L, 3.0L, 4.0L) and options, it's impossible to give a precise location. The owner's manual is crucial for this information.
