Transfer Pump Fuel Volume Check
- Turn ignition off. To check transfer pump (in tank), remove rear seat. Remove fuel sending unit access cover. Disconnect ignition coil secondary wire and jumper to ground.
- With transmission in Neutral, crank engine for 3-4 seconds. While starter is turning and for a few seconds afterwards, an audible sound should be heard at the pump. If sound is not heard, go to next step. If sound is heard, go to step 5).
- Remove fuel pump relay from relay panel. On Corrado and Passat, activate fuel pumps using Remote Control (VAG 1348/3A). On all other models, activate fuel pumps using Remote Control (US 4480/3). On all models, if pump does not operate, remove transfer pump wire harness connector. See Fig 1 .
- Using test light, check voltage between middle wire and outer Brown wire of fuel pump connector for Digifant fuel system, or between Brown wire and Red/Yellow wire for CIS-E fuel system. If voltage is present, replace transfer pump. If voltage is not present, repair open or short circuit in wiring.
- Remove fuel pump relay jumper wire. Disconnect and plug transfer pump output hose. Attach a hose to pump outlet connector and place other end of hose in a graduated container. Activate fuel pump for 10 seconds.
- Minimum fuel flow should be 10 ounces (.3 liter). If fuel flow is low, check fuel tank filter for restriction. If fuel tank filter is okay, replace transfer pump.