Audi Says No-Go

This bulletin applies to 2009 Audi A5/S5 models where an engine no-start condition is experienced, despite pressing the clutch pedal. The driver information center permanently shows the message “To start engine press clutch.”

When pressing the clutch pedal, an additional pressure point can be felt just before full stop. In this position, a start is not possible. The pedal can be depressed about 1cm (25/64-inch or 0.3937-inch) past this pressure point. The interlock switch in the clutch master cylinder only then authorizes the start.

This example shows that the plastic cover of the release bearing’s thrust washer has worn off.

Because of a malfunction of the interlock switch in the clutch master cylinder, the start is not authorized.

When the release bearing is worn or the release bearing presses against the release lever, the mechanical ratio of the clutch mechanism increases. This causes the hydraulic ratio to increase too much, which leads to the additional pressure point.

Check the interlock switch in the clutch master cylinder. If the interlock switch is incorrect, replace the clutch master cylinder. The interlock switch is calibrated to the clutch master cylinder and cannot be replaced individually.

Check whether there is an additional pressure point in the clutch pedal travel. If this is the case, check the components of the mechanical and hydraulic clutch mechanism for wear/damage. Replace any worn or damaged parts.

If the release bearing or release lever shows wear marks, replace both parts. Be sure to also replace the guide sleeve for the release bearing whenever the bearing is replaced.

Do not mix shift forks/pivot points. P/N 0B1 141 719H lever should only be used with ball pin 0B1 141 777 A. P/N 0B1 141 719 J lever should only be used with ball pin 0B1 141 777 B.

In this example, the release bearing has pressed against the release lever. Note the wear marks.	During assembly, be sure to lubricate the bearing, lever, sleeve and ball pin.