Circuit Description
Ignition control assembly is located on valve cover of each cylinder bank. Each assembly (there are 2) contains a control module and 4 ignition coils. Each coil connects directly to spark plug, eliminating secondary ignition wires. Each module has a reference low circuit to PCM. PCM uses IC circuits to send timing pulses to ignition control module. This signals ignition module to trigger coil and fire spark plugs.
PCM check IC circuits for an improper voltage condition. PCM is able to separately detect IC circuit shorted to ground. However, PCM cannot separately detect a short to voltage or open circuit. Therefore, PCM detects IC circuits for this condition in 2 groups. The 2 groups consist of every other cylinder in engine firing order (1-7-4-6-2-3-5-8). DTC will set if PCM detects an improper voltage condition in circuit group for cylinders No. 1, 4, 6 and 7.