System Check - Distributor Ignition (DI)

Diagnostic Chart:

Wiring Diagram:

DIAGNOSTIC AIDS

An ignition coil wire that is open or shorted to ground can cause a no start condition.

TEST DESCRIPTION

Number(s) below refer to step number(s) on the diagnostic table.

IMPORTANT: The battery should be fully charged prior to any tests.

2. Checks for proper output from the distributor ignition system. The spark tester requires a minimum of 25,000 volts to fire. This check can be used in case of an ignition miss, because the system may provide enough voltage to run the engine but not enough to fire a spark plug under heavy load.

4. This test will separate the distributor cap, rotor and ignition wires from the ignition coil to help identify a secondary ignition system problem. It is necessary to unscrew the top terminal on the ST-125 spark tester for a proper fit in the distributor end of the coil wire.

5. This will determine if the proper available voltage exists in the primary ignition circuit.

7. This check will begin to determine if the PCM is providing a signal to the ignition coil module or not. If the PCM is not providing a signal to the ignition coil module, the problem exists between the distributor and PCM.

12. If the PCM is detecting low resolution signal pulses and no Ignition Control(IC) signal was available at the ignition coil module, a problem exists with the PCM or the circuit to the ignition coil module.

13. If the PCM does not detect low resolution signal pulses, the distributor or distributor to PCM circuitry is most likely the problem. The remaining tests will determine if the proper signals are being sent and received from both the distributor and PCM.

22. A grounded coil circuit will cause the ignition fuse to open, and a no-start condition will occur.