2003-2004 A4 Cabriolet 1.8 Liter 4-Cyl. 5V Turbo Generic Scan Tool

- Disconnect the 4-pin harness connector -1- at one ignition coil -2-. Note: For further testing, connect the multimeter to harness connector in place of an ignition coil. - Connect multimeter for voltage measurement as follows. Harness connector Measure to Terminal 1 Engine Ground (GND) - Switch ignition on. Specified value: approx. battery voltage - Switch ignition off. If specified value is not obtained: - Remove rubber seal for plenum chamber cover. - Remove plenum chamber cover -1- toward front (arrows). - Pry off both covers -3- using a screwdriver. - Loosen hex-nuts -4- by several turns. - Loosen wiper arm -2- from wiper axle by lightly tilting. - Remove hex nuts completely and remove wiper arms. - Disconnect securing clips -1- and remove cowl grill -5-. - Remove cover for E-box, plenum chamber (arrows). - Pry off Engine Control Module (ECM) retaining bracket (arrows) using a screwdriver and set control module aside. - If installed, unclip Transmission Control Module (TCM) retaining bracket and set control module aside. - Disconnect voltage supply relay -3-. - Check the following wire connection for open circuit according to wiring diagram: Relay carrier in E-box, plenum chamber, position 3 Terminal Harness connector at ignition coils Terminal Specified value: Wire resistance max 1.5 - If necessary, repair wire connection. If no malfunctions are found in wires: - Check voltage supply of Motronic Engine Control Module (ECM) voltage supply relay - J271 - Check activation of Motronic Engine Control Module (ECM) voltage supply relay.

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