Brake pressure pump

Check the relays....sounds like one is stuck.

I think it will be over on the pass. side firewall, near the service connector. That linked article should cover that as one of the troubleshooting issues.

The failure of the Hydraulic Pump Motor Relay is a common occurrence. The normal failure modes are the contacts welded themselves shut causing the Hydraulic Pump Motor to run continuous or the relay failing to close which prevents normal pump motor operation. To verify relay operation it would be possible to disconnect the harness connector to the Anti-Lock Pressure Switch and ground pin 4 of the connector to ground.(See Figure 5) This will complete the circuit for the coil of the Hydraulic Pump Motor Relay and should cause the pump to turn on. If the pump does not run most likely the relay is bad and must be replaced. If the motor does run the Pressure Switch may be the faulty part and should be replaced. The FORD Shop Manual states that if the Pressure Switch is replaced the Hydraulic Pump Motor Relay should be replaced as well.
 
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not sure why, but i had that relay go bad about every 6months until i converted the brake system to conventional. have a back up on hand in the car with you.
 
not sure why, but i had that relay go bad about every 6months until i converted the brake system to conventional. have a back up on hand in the car with you.

Sounds like cheap/mismatched relays - I replaced mine only as I didn't know how old it was, and that was four years ago. I only carry a AAA card - zero trunk spares :)
 
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