The ignition system uses individual ignition coil/module assemblies for each cylinder. The Powertrain Control Module (PCM) controls the individual coils by transmitting timing pulses on the Ignition Control (IC) circuit of each ignition coil/module to enable a spark event. The PCM monitors each IC circuit for improper voltage levels. Each ignition coil/module has the following circuits: An ignition voltage circuit, a ground, an IC circuit, and a low reference circuit.
If a problem with the ignition is intermittent, inspect for the following:
If a fault is found, make the appropriate repairs.
2.0L & 2.4L Engines
This no-start test checks the camshaft position sensor and crankshaft position sensor.
The Powertrain Control Module (PCM) supplies 8 volts to the camshaft position sensor and crankshaft position sensor through one circuit. If the 8-volt supply circuit shorts to ground, neither sensor will produce a signal (output voltage to the PCM).
When the ignition key is turned and left in the ON position, the PCM automatically energizes the auto shutdown (ASD) relay. However, the controller de-energizes the relay within one second because it has not received a camshaft position sensor signal indicating engine rotation.
During cranking, the ASD relay will not energize until the PCM receives a camshaft position sensor signal. Secondly, the ASD relay remains energized only if the controller senses a crankshaft position sensor signal immediately after detecting the camshaft position sensor signal.
- Before servicing the vehicle, refer to the Precautions section.
- To perform the test:
- Battery voltage should approximately 12.66 volts or higher.
- Disconnect the harness connector from the coil pack
- Connect a test light to the B+ (battery voltage) terminal of the coil electrical connector and ground.
- The B+ wire for the DIS coil is the center terminal. Do not spread the terminal with the test light probe.
- Turn the ignition key to the ON position. The test light should flash on and then off.
- If the test light flashes momentarily, the PCM grounded the ASD relay.
If the test light did not flash, the ASD relay did not energize.
- The cause is either the relay or one of the relay circuits.
Crank the engine.
NOTEIf the key was placed in the off position after step 4, place the key in the on position before cranking. Wait for the test light to flash once, then crank the engine.
- If the test light momentarily flashes during cranking, the PCM is not receiving a crankshaft position sensor signal.
- If the test light did not flash during cranking, unplug the crankshaft position sensor connector.
Turn the ignition key to the off position. Turn the key to the on position, wait for the test light to momentarily flash once, then crank the engine.
- If the test light momentarily flashes, the crankshaft position sensor is shorted and must be replaced.
- If the light did not flash, the cause of the no-start is in either the crankshaft position sensor/camshaft position sensor 8 volt supply circuit, or the camshaft position sensor output or ground circuits.