Fuel Pump Relay Control
- With ignition off. Remove fuel pump relay from relay panel. Connect voltmeter between relay terminals No. 48 and 50. Voltmeter should read 12 volts. See Fig 1
.
- If reading is not as specified, repair break in wiring. Connect voltmeter between relay terminals No. 46 and 50. Turn ignition on. Voltmeter should read should 12 volts.
- If reading is not as specified, repair break in wiring. Connect voltmeter between relay terminals No. 46 and 47. Momentarily engage starter and note reading on voltmeter. Reading should be 7 volts.
- If reading is not 7 volts, partially remove ICU and disconnect harness connector. Using an ohmmeter, check continuity between ICU terminal No. 3 and relay terminal No. 49, and between ICU terminal No. 14 and terminal No. 47. Readings should be less than .2 ohm.
- If readings are not as specified, repair break in wiring(s). If readings are as specified, replace knock sensor.
Courtesy of AUDI OF AMERICA, INC.