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2jzgte cranking no-start. Wired, cranking, 5v ref present, injector pulse present but only getting spark on coils 1+2. Using an incandescent test light I was able to make the igniter fire all the coils.
Explanation: The 2jzgte uses an ignition module/ignitier to fire the coil with a 0-5 volt (v) square wave signal from the pcm/brain. I being able to fire the coils using the test light at the PCM would prove the following: igniter good, coils good, wires "connected".
Ok so the coils fired using the test light so rpm signal inputs, cams and crank, had to be confirmed. They checked good. Pcm signal to igniter had to be confirmed but a low 0-1v squarewave was seen. Low output from the pcm would mean circuit shorted to ground or low power feed. It was late & I was tired so I opted to check the easier one, power feed. The 2 power wires read 8v vs system voltage of 12.5. Further tests showed EFI fuse bad.
After replacing fuse, the PCM was producing full 5v square waves on all igniter wires. So wth only 1 & 2 firing? Half drunk with sleep I went to the igniter with the scope and discovered that the 5v signal was not reaching it for the coils that weren't firing. So guess what. I have to go make a patch harness and bypass the corroded wires.
After doing the patch I discovered that when the ignitor is plugged in the squarewave is very low but unplugged it's back to 5v. Anyone ever experience an ignitor shorting the igt signal for coils?
