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When the Check Air Suspension warning comes on the control module has detected a fault with the system and will store a code. A Ford factory scan tool will be needed to read this code. I first recommend that you check fuses f1.10 (10 amp), f1.114 (30 amp)and the relay located in the battery junction fuse box and fuse f2.8 (10 amp) in the central box behind the dash.
After checking all fuses and relays the air suspension is still not operating.
The pump is fine as I can direct wire it and operate it. the relief side of the pump is also working.
Is there anthing else I can check other than the limit switch at the rear axel?
What kind of readings should I be getting at the connection? 12 volts or MV?
can you supply a wiring diagram for this circut?
I am hoping to see where the voltage comes from to the body positional switch at the rear axel.
It comes from the module.