13-08-14, 08:10 PM
The high side of the coils is attached permanently to 12V. Normally these 12V come out of the loom, but affected by a severe drop due to cable length, fuses and swiches. The relay makes a direct connection to the battery and gives clean 12V.
The low side of the coils is switched by the ECU, causing the spark.
By my estimate and experience the relay gives a gain of about 2V at the coils.
The low side of the coils is switched by the ECU, causing the spark.
By my estimate and experience the relay gives a gain of about 2V at the coils.