How can I test the Hall Effect switch in a 1990 Jetta Carat? Mitchell on demand says to use a "LED Test Light" on the middle terminal to see if it blinks while turning over the engine, But I can only find that test light from snap on for around $80.00. I got a rebuilt distributor because the connector was damaged and I was getting an intermittant ignition pulse but now I have nothing. Voltage at the outer prongs but no spark.