The C(3)I system uses waste spark method of spark distribution. In this type of ignition system, ignition module triggers No. 1 and 4 coil, resulting in both No. 1 and 4 spark plugs firing simultaneously. The No. 1 cylinder is on compression stroke at the same time that No. 4 is on exhaust stroke, resulting in a lower energy requirement to fire No. 4 spark plug. This leaves the remaining high voltage to fire No. 1 spark plug. The sequential fuel injection type of fuel delivery system utilizes 6 separate injector "driver" circuits to activate 6 fuel injectors. While cranking, ECM activates all 6 injector "driver" circuits simultaneously. After a calibrated engine RPM is reached, and a good camshaft signal has been received by ECM, the injection mode of operation is changed to sequential (sprayed in spark plug firing order). Fig. 15: Chart A-3, Wiring Diagram Engine Cranks But Will Not Run (1 of 4) 1. This test verifies that "SES" light operation, TPS and coolant sensor signals are normal. A blinking injector test light verifies that ECM is monitoring C(3)I reference signal and attempting to pulse injectors. 2. The crank sensor has been verified as functioning properly. Performing a fuel pressure test will differentiate between fuel related or ignition system problem. 3. By testing for spark on plug leads 1, 3 and 5, each ignition coil's ability to produce at least 25,000 volts is verified. If engine starts, runs for several seconds and dies repeatedly, consider this to be no spark at all. 4. Checking faulty coil's control circuit using a test light, will determine whether coil is faulty, or module's internal driver for that coil is at fault. 5. This test checks for battery voltage at circuit No. 639. If voltage was present, "light off" test result was caused by no activation pulse reaching injector connector from ECM. 6. If fuse was blown, check circuit No. 839, which includes fuel pump relay, fuel pump and wiring, to determine cause of high current flow. 7. Test light to 12 volts simulates a reference signal to ECM. This results in an injector test light flash with each contact of test light probe to terminal "D". It may take up to 3 probe contacts to flash test light. If test light flashes, circuit No. 430, ECM and injector driver circuits are functioning properly. 8. If crank sensor signal circuit terminal "A" is momentarily jumpered to ground circuit terminal "C", and engine is cranked without turning ignition off, the response should be an injector test light flash. The ignition module will then transmit fuel control signal to ECM while cranking. Allowing generation of reference signal to ECM terminal "BD8", and ECM to activate injector driver circuit. 9. This test verifies proper sync-signal circuit voltage of 9-12 volts, and a proper ground from C (3)I module to terminal "C" of sensor connector. 10. Determines if reason for incorrect voltage reading was due to fault in circuit No. 645 or faulty C(3)I module. 11. Jumping crank sensor harness terminals "A" and "C" together, simulates a sync signal to ignition module. By jumpering crank sensor harness terminals "B" and "C" together, a crank signal is simulated. This signal will then cause ECM to energize fuel pump relay for 2 seconds (it should click on and off) and injectors should be heard clicking on and off. 12. Verifies a proper crank signal circuit voltage of 9-12 volts and a good ground from ignition module to terminal "C" of sensor connector. NOTE: Test numbers refer to test numbers on diagnostic chart. 13. Determines if reason for incorrect voltage reading was due to a fault in circuit No. 643, an open in circuit No. 645, or a faulty ignition module. BTW check email, charts sent in PDF format. Let us know how you make out. I don't theink it's security problem unless the light never stops blinking?
Wednesday, September 2nd, 2009 AT 3:12 PM