* Check Engine Light (CEL): This is the most common indicator. A malfunctioning ignition coil will trigger the CEL, and a diagnostic scan tool will be needed to determine the precise code and identify the faulty component.
* Misfire: A bad ignition coil will cause a misfire in one or more cylinders. This might be noticeable as rough running, hesitation, loss of power, or a shaking sensation.
Therefore, if you're seeing a light on your Ford Transit dash and suspect an ignition coil issue, you need to identify the *specific* light (e.g., the Check Engine Light symbol) and then have the vehicle diagnosed using an OBD-II scanner. A mechanic will be able to pinpoint the problem.