Brad's Car Manuals: A 3rd party mirror of CHARM + LEMON car manuals
Home >> Audi >> 1989 >> 90 Base, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Basic Testing >> Fuel System >> Fuel Pressure (Cis Digital Control) >> Fuel Pump Relay

Fuel Pump Relay

Download the full database via torrent (~1.1 TB)
  1. Remove fuel pump relay from relay board. Turn ignition on. Test light should light when connected between socket for relay terminal No. 46 and ground. See Fig 1 .
  2. While starter motor is operating, test light should flicker when connected between sockets for relay terminals No. 50 and 51. Test light should light when connected between sockets for relay terminals No. 46 and 50. Test light should light when connected between sockets for relay terminals No. 46 and 52.
  3. If test light does not light up for all tests, check wiring for continuity. If test light does light up for all tests but there is no voltage at fuel pump with relay installed, replace fuel pump relay.
Fig 1: Checking Fuel Pump Relay Circuits
G94328Courtesy of AUDI OF AMERICA, INC.