Diagnostic Overview

WARNING: This page does not describe the selected car, but rather 10 other vehicles, including the 2010 BMW M6, 2010 BMW M5, 2009 BMW M6, 2009 BMW M5, and 2008 BMW M6. However, it is still accessible from the selected car via links, so may be relevant.

Each camshaft (CAM) has a tooth wheel with six teeth. The sensor converts each tooth to a signal with a rising and falling edge. Each falling edge of the camshaft sensor (oncoming tooth) is a signal for the CAM position relative to crankshaft.

The inlet CAM's have a periodical tooth's spacing with 6 times 60°angle to measure the camshaft position.

The outlet CAM's has an additional function:

Synchronize the crankshaft with the CAM.

So, the outlet CAM's have a different angle for each tooth.

To synchronize the crankshaft with the CAM, after the missing teeth of the crankshaft the level of the CAM senor (high or low) signs the right synchronization.

A plausibility diagnosis is performed that compares the outlet CAM sensor level after each missing tooth of the crankshaft. The CAM sensor must different levels after each complete crankshaft revolution. If not, a CAM synchronization error is stored.

If a CAM synchronization error is detected, the synchronization is made with the ion current signal:

The ignition is switched to 360° mode. The ion current is also measured every 360° for each cylinder. But combustion occurs only every 720° and is detected with the ion current. So the CAM synchronization can be determined.

There is an additional plausibility check for each CAM sensor:

The number of teeth for two complete crankshaft revolutions is counted. If there are too much or too less tooth's, a sensor error is stored.

If so, the CAM's position can't be measured correctly and all CAM's are positioned at their save positions.

See the summary table for further explanation of this monitor.