Possible Causes

2021 Ford Edge SE, 4WDSECTION Possible Causes
WARNING: This page is about a different car, the 2020 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
  • Wiring, terminals or connectors
  • HydroMax pump motor relay
  • ABS module
  1. CU1: CHECK PUMP MOTOR RELAY COIL GROUND CIRCUIT FOR AN OPEN 
    • Ignition OFF.
  2. CU2: CHECK PUMP MOTOR RELAY COIL GROUND CIRCUIT FOR A SHORT TO GROUND 
    • Measure the resistance between:
      (+) HydroMax Relay Connector, Harness Side (-)
      HRC Ground
    • Is the resistance greater than 10, 000 ohms? 
      Yes No
      Go to  CU3. REPAIR the circuit.
  3. CU3: CHECK PUMP MOTOR RELAY COIL GROUND CIRCUIT FOR A SHORT TO VOLTAGE 
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) HydroMax Relay Connector, Harness Side (-)
      HRC Ground
    • Is any voltage present? 
      Yes No
      REPAIR the circuit. Go to  CU4.
  4. CU4: CHECK FOR CORRECT ABS MODULE OPERATION 
    • Ignition OFF.
    • Inspect the ABS module electrical connector and the HydroMax relay socket.
    • Repair:
      • corrosion (install new connector, socket or terminal - clean module or relay pins)
      • damaged or bent pins - install new terminals or pins
      • pushed-out pins - install new pins as necessary
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.