Contents Wiring diagrams Section: 1.8l 4-cyl 5v Turbo Engine Controls - Fuel Injection & Ignition, Engine Code(s): Amb All sections

Checking activation Audi A4 B7

Checking activation

  1. Connect multimeter as follows to measure voltage.
Relay carrier in electronics box, plenum chamber, position 2 TerminalMeasure to
6Battery positive (B+)
  1. Switch ignition on.
  1. Specified value: approx. battery voltage (B+)

If specified value is not obtained

  1. Switch ignition off.
  2. Connect test box V.A.G 1598/31 to wiring harness for ECM; do not connect ECM. Refer to «Electrical testing using VAG1598/31 test box»(/audi/a4/b7-2004-2009/remont/blowers-superchargers-turbochargers/#18l-4-cyl-5v-turbo-engine-controls-fuel-injection-ignition-engine-codes-amb__electrical-testing-using-vag159831-test-box) .
  1. Check for open circuit, short to positive, or short to ground in following wiring connection(s)
Relay carrier in electronics box, plenum chamber, position 2 TerminalTest box V.A.G 1598/31 Socket
621
  1. Repair any open/short circuit as necessary.

If no malfunction is found

  1. Replace Motronic ECM power supply relay -J271-.