Checking actuation

• Connect multimeter as follows to measure voltage.
  ECM POWER SUPPLY RELAY CIRCUIT TEST: ACTUATION
  
  

  Relay carrier in electronics box, plenum chamber, position 2 terminal	Measure to
  4	Battery positive

Fig 1: Identifying Power Supply Relay Harness Connector Terminals
Courtesy of AUDI OF AMERICA, INC.
• Switch ignition on.
  • Specified value: approx. battery voltage

If specified value is not obtained:

• Switch ignition off.
• Connect test box VAG1598/31 to wiring harness for engine control module; do not connect engine control module. See WIRING AND COMPONENT CHECK WITH TEST BOX VAG1598/31 .
  Fig 2: Identifying Power Supply Relay Harness Connector Terminals

  Courtesy of AUDI OF AMERICA, INC.
• Check for open circuit and short to positive or short to ground in following wiring connection:
  ECM POWER SUPPLY RELAY CIRCUIT TEST: OPENS/SHORTS
  
  

  Relay carrier in electronics box, plenum chamber, position 2 terminal	Test box V.A.G 1598/31 Socket
  4	23

• Repair any open/short circuit as necessary.

If no malfunction is found:

• Replace Motronic ECM power supply relay -J271-.