Derby 1999 problem burning

I have a problem with a 1999 model derby, the problem is that the coil module is on heating and burn or break down and no longer gives spark, the hall sensor sends pulses and already checks the feeding, ngative, the positive one gives about 7V and what makes me strange is that in the sensor signal cable it has the same voltage of 7v chc chcando with multimeter Leds test in PIN + does not turn on the lamp, already check resistance and possible shorts in the harnes and nothing, check the same voltges from the computer connector and it does not matter, something else is that the board the tacometer the needle only stays dancing in the part of the 0, on the side of the coil everything seems to be ok, the relays seem ok and already check it
... Does anyone have the workshop manual or someone who has happened to my problem ???

I had a vehicle that burned the coils and was the fault of the spark plug in poor condition, and on another occasion it was the guilt of the engine temperature, but the issue of burned modules goes through bad refrigeration can move inside the vehicle to look for a better position a good electric can do it.