Fuel Pump "A" Control Circuit/Open

Possible causes

• CommonFailed relay
• CommonCorroded relay socket or fuse box connections
• CommonWiring fault between the module and the relay
• CommonWater ingress into the fuse box
• PossibleBlown fuse
• RareFailed control module driver
• PossibleFailed fuel pump
• PossibleCorroded earth at the pump

What you might notice

• Engine will not start
• Cutting out while driving
• Loss of power under load
• No fuel pump noise when the ignition is switched on
• Battery flat after standing

What to check, in order

1. Listen for the pump. Switch the ignition on without cranking - a working pump runs for a second or two. Silence is a clear finding and costs nothing to check.
2. Swap the relay with an identical one from elsewhere in the box and see whether the fault follows it. It costs nothing and is the fastest test available.
3. Inspect the relay socket for corrosion, heat damage and spread terminals - a discoloured socket means the relay has been running hot.
4. Check the fuse for the circuit.
5. Check the fuse box for water ingress, particularly if it is mounted low or in the engine bay.
6. Check the wiring between the module and the relay.