NOTE: No testing procedure was available from manufacturer for 5-cylinder Volkswagen models.

Remove fuel pump relay from relay board. Turn ignition on. Using multimeter, measure voltage at following relay board sockets: between terminal No. 2 and ground, between terminals No. 2 and 1 and between terminals No. 4 and 1. Reading should be battery voltage or slightly less.
If reading is low or zero, check wiring. Refer to WIRING DIAGRAMS to check circuits. Measure voltage between relay board sockets No. 5 and 1. Battery voltage should be present. If reading is correct, ground middle wire of ignition distributor connector.
Voltage reading should drop for short time. If reading does drop, replace relay. Reading should be battery voltage or slightly less.
If reading is low or zero, check wiring. Refer to WIRING DIAGRAMS to check circuits. Measure voltage between relay board sockets No. 5 and 1. Battery voltage should be present. If reading is correct, ground middle wire of ignition distributor connector.
Voltage reading should drop for short time. If reading does drop, replace fuel pump relay and check Hall sender. If reading does not drop, check Hall ignition ECU.

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.

Safety Warning

Fuel Pump Relay - 4-Cylinder Models