Skoda Fabia 1.2L 2005 cutting out and non start until fuse replaced.
A reasonably simple problem, but quite nice as a casefile, as it really illustrates the potential for failure of the component.
When I came to this vehicle, it was a non start and the fuse for the ignition coils had blown. I replaced the fuse and started the car.
The car started just fine, it ran a little lumpy and the fuse blew again after a short time running.
So I set up the scope using just a current clamp. I managed to get the clamp on a section of harness right at the ignition coil wiring on the top of the engine.
As can be seen, this capture quickly showed a problem in the ignition coil pattern. So I went on and disconnected a coil to trace which one was the real problem. I started with cylinder 3.
I struck lucky first time! As you can plainly see, the current ramp pattern instantly changed and the car continued to run until I switched it off.
We’ll have a look in more detail.
You can see here that the coil for cylinder 3 is pretty close to a ‘dead short’, but 1 and 2 are not even.
I left this car with the garage, with the recommendation of a set of coils. I don’t know whether they were all changed or just the one, but my work was done.