Part 1 of 2

Chart A-3 Part 1 Of 2:

Ignition & Fuel Injection Wiring Schematic:

CIRCUIT DESCRIPTION
If the Tech 1 scan tool did not indicate RPM during cranking, and there is no spark present at the plugs, the problem lies in the direct ignition system or the power ground supplies to the module.

The magnetic crank sensor is used to determine engine crankshaft position much the same way as the pick-up coil did in distributor type systems. The sensor is mounted in the block near a seven slot wheel on the crankshaft. The rotation of the wheel creates a flux change in the sensor which produces a voltage signal. The ignition module then processes this signal and creates the reference pulses needed by the Powertrain Control Module (PCM) and the signal triggers the correct coil at the correct time.

CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.

1. A Malfunction Indicator Lamp (MIL) "Service Engine Soon" "ON" is a basic test to determine if there is a 12 volts supply and ignition 12 volts to PCM. No DLC may be due to a PCM problem. If Throttle Position (TP) sensor is over 2.5 volts, the engine may be in the clear flood mode which will cause starting problems. The engine will not start without reference pulses and therefore the Tech 1 scan tool should read RPM (reference) during crank.
2. For the first few seconds with ignition "ON," or whenever reference pulses are being received, Tech 1 should indicate fuel pump circuit voltage (8 to 12 volts).
3. Because the direct ignition system uses two plugs and wires to complete the circuit of each coil,the companion plug should be left connected. If RPM was indicated during crank, the ignition control module is receiving a crank signal, but no spark at this test indicates the ignition control module is not triggering the coils.
4. This test will determine if there is B+ at the injectors. The injectors are powered by a 20 amp fuse located at fuse block.
5. This test will determine if the ignition control module is not triggering the suspect coil, or if the tested coil is at fault. This test could also be performed by using another known good coil.
6. This test will determine if the ignition module is not generating the reference pulse, or if the wiring or PCM are at fault. By touching and removing a test light to 12 volts on CKT 430, a reference pulse should be generated. If RPM is indicated, the PCM and wiring are OK.