How do you check the voltage on a car coil?
Make sure all connections are clean and tight. To check that voltage is reaching the coil, connect the voltmeter between the + or SW terminal of the coil and earth, and switch on the ignition. The meter should read nearly 12 volts, or about 7 volts if the coil has a ballast resistor.
Do you need to replace the exciter coil?
The crank position sensor and exciter coil often must be replaced with the stator as an assembly. Inspect the ignition system related switches for correct continuity according to the service manual or wiring diagram. This usually includes the main (ignition) switch, engine stop switch, and side stand switch.
How much voltage does a negative earth car have?
Instructions here are for the more common negative-earth system: with a positive-earth car read – for + and + for – throughout. A ballast resistor allows extra voltage for starting, relieving the strain on the battery – especially in cold weather. The voltage reaching the coil may be 12 volts , or about 7 volts if the coil has a ballast resistor .
How can I tell if my coil has a short circuit?
Connect the meter between the or CB terminal of the coil and earth, and switch on the ignition. Again the meter should read about 12 volts. If it reads zero there may be a break inside the coil winding, or a short circuit to earth inside the distributor or in the LT lead. Check further by disconnecting this LT lead and repeating the test.
What to do if there is no spark at the coil?
Test for voltage from the ignition switch at the positive side of the coil. Refer to the above image. If there’s no voltage, check the wire between the ignition switch and the coil and, if necessary, the switch itself. If there’s voltage, the problem may be with the pickup unit.
What should the resistance be on a Delco ignition coil?
This reading of 8.84 does indicate that the coil’s secondary windings are not putting out as much voltage as they should; the minimum acceptable resistance reading here should be 11.00, with approximately 13.5 being normal. Here’s the primary reading on the new replacement GM Delco coil before I installed it.
What to do if your DMM doesn’t register voltage?
Author’s own drawing. Turn the ignition switch to On or Run. If the testlight stays off or the DMM doesn’t register any voltage, either the coil’s primary winding has an open or the circuit between the ignition switch and the coil’s battery terminal has an open. Consult your repair manual.
How can I check the resistance of my ignition coil?
You’ll need a digital multimeter to check the resistance levels of your coil. The side terminals of the coil are marked positive (+) and negative (–) and these are where you can measure the resistance of the primary windings.