You are most correct! You will find that relay control circuits are fused on different circuits than the actual load circuits.
Example, on the CRD the AC compressor clutch itself is supplied power through fuse 21 (8W-10-25) in the Power Distribution Center supplied by the battery (8W-10-10) while the control side of the circuit to the AC compressor clutch relay is supplied power from fuse 16 (8W-10-19) which gets its power from fuse 6 coming through the Auto Shut Down Relay. (8W-10-19)
If he is blowing fuse 16 as soon as the ignition switch is turned to the on position, these are the circuits it supplies power to:
1. AC compressor clutch RELAY
2. Low speed radiator fan RELAY
3. High speed radiator fan RELAY
4. Cabin heater RELAY
5. Front Control MODULE
6. Engine Control MODULE
7. EGR solenoid
8. EGR air flow control
9. Vacuum Reservoir solenoid
10. Boost pressure solenoid
11. Glow plug MODULE
If you unplug all of these items listed above and it still blows fuse 16 when the ignition switch is turned on, then you have a wiring harness short where a wire is either touching a ground somewhere or has rubbed into another wire in the harness that is a ground wire....
Good luck!
_________________
Supporting Vendor and Moderator of LOST05 Jeep Liberty CRD Limited
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