No, the failure mode starts when the ground level at the coil is about 2.5 volts or more above the ground at the ECU. Then the coil's driver turns on and drives the coil's primary to saturation. This becomes a static condition(ECU no longer has dwell control) and slowly overheats the coil module. At this point some of the drivers fail with the input shorted to the output(neg. side of coil). At no point has the peak current through the coil gone higher than normal, its just that its "ON" 100% of the time, that causes the thermal runaway.
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