How to Test Crankshaft and Camshaft sensors 1 Amazon Printed Books https://www.createspace.com/3623936 Amazon Kindle Edition http://www.amazon.com/Automotive-Test... Android APPs https://play.google.com/store/apps/de... Shows the operation and testing procedures of automotive cam and crk sensors, which supply the ECM with engine camshaft and crankshaft position. These two signals are essential for the engine to run. (note: We allow all schools and training institutions to use our software free of charge, so long as it is not sold to others. You're encouraged to download our free automotive simulation software for more information.