Differential Pressure Regulator Electrical System

1. Connect Pressure Gauge (VW 1318) as described above in SYSTEM PRESSURE heading above. See Figure . Close pressure gauge valve. Disconnect differential pressure regulator harness connector.
2. Using Adapter (VW 1315 A/1), connect Multimeter (US 1119) to differential pressure regulator and harness connector. See Fig 1 .
3. Set multimeter to 200 mA DC scale. Turn ignition on. Multimeter should read 100 mA. Pressure gauge should read 17-22 psi (1.2-1.5 kg/cm² ) less than pressure noted in SYSTEM PRESSURE heading above. If pressure is not as specified, check differential pressure regulator wiring and connectors. If wiring and connectors are good, replace differential pressure regulator.

Fig 1: Attaching Multimeter to Differential Pressure Regulator

Courtesy of AUDI OF AMERICA, INC.