Has anyone ever heard of a advancing timing light taking out a Thunderbolt 5 module. I'm a Tech and just can't see how this would be possible. I could see it if there was a hook up to the distributer but were talking a inductive pick-up and + and - to the batt.
I have a Merc tech friend that strongly advises against it. He says he has heard of this more than once.

Anyone have the # to Merc I would like to call them and find out the facts. Thanks Scott

Ha never hered of that myself, and I have a Mac light aand I have used it to check total timing on my 1995 330 Hp motor that is all stock

I would have to say that is impossible. The light has absolutely nothing to do with the distributor or module. It only changes the timing of the flash of the light so that you can use the zero mark on the balancer instead of the timing marks to measure the actual timing of the engine. Nothing is connected to the engine except the inductive pickup on the #1 spark plug wire. All timing lights do that. I would like to hear the explanation from the Merc tech on that one.

Man i have not heard that one before. If you find out for sure keep us posted.

I totaly agree with you guys It makes no sense at all but the person this came from is reputable. He does admit he doesn't grasp the electronic end of things like he should.

This is my guess
Someone used a older light that hooked up to the distributer (tach) and the other lines to the usual spots #1 and power. Some how he took out the module by hooking it to the wrong spot or they had the purple wire grounded out taking the advance out of the timing. Start of wives tale