Checking the contactless ignition system switch (Audi 80 B2)

Disconnect the wires from the digital idle stabilizer move (if it is installed) and connect them together.

Disconnect the central high-voltage wire from the ignition distributor sensor and short it to ground.

Disconnect the spark plug sensor connector.

Connect the voltmeter to terminals "15" ("+") and "1" ("-") of the ignition coil.

Turn on the ignition and measure the voltage, which should remain within 5-6 V for 1 s, then drop to zero.

If the voltage exceeds 1 V for more than 1 s, turn off the ignition immediately. In this case, the switch is faulty and must be replaced.

Briefly short-circuit the central (green) wire of the ignition distributor sensor block to ground and measure the voltage, which should briefly increase to 5-6 V. If this does not happen, the switch is faulty and must be replaced.

Turn off the ignition.

Connect the voltmeter to the outer red and brown wires of the ignition distributor sensor block.

Turn on the ignition and measure the voltage, which should be at least 10 V. If the voltage does not correspond to this, the switch is faulty and must be replaced.