The ignition coil is one of the most important and reliable elements of the ignition system. It is rarely the culprit of malfunctions, so you need to check its serviceability at the very last moment.
Instructions
Step 1
To begin with, carefully inspect the coil and check the surface for contamination that can lead to the fact that the voltage goes to ground. After that, pay special attention to the coil body. If there are oil stains on it, then this is a sign that there is dirt on the cover, which will lead to the final failure of the part. Also check the leads of the wires, which should not show any signs of oxidation or rust.
Step 2
If you have a contact ignition system installed, then the coil is checked for serviceability by installing a central high voltage wire at a distance of 5-7 mm from the car body, which is a mass. If the coil is fully operational, a blue spark appears at the moment the contacts open. Otherwise, there will be no spark, or it will be very weak.
Step 3
Measure the resistance of the windings and insulation of the coil, which should correspond to the values indicated for this type of vehicle. If you do not have such data, then the insulation resistance should be about 50 mOhm, and the resistance of the primary winding is about 5 Ohm, provided that the voltage across it is 12 Volts.
Step 4
Check the reliability of the coil insulation, as well as the polarity of the wires, if they are reversed, then correct this deficiency. Check the primary winding with an ammeter by measuring the current in the circuit. After that, turn on the ignition and close the breaker contacts. In this case, the current strength must be within the limits specified for this vehicle. If the measured value is greater than this value, then this indicates that the winding is broken.
Step 5
When installing the coil in its place, be careful not to mix up the wires, which otherwise can lead to its damage and burning of the breaker contacts, and in the worst case, to a short circuit.
