Code P1300 igniter circuit malfunction

Thanks Danny, this car is away with my son at university. I will go out there and run through the diagnostic. The car will not start, and my son reports that it drove fine, then it was parked and now will not restart.

Also, a favor, is there a diagram of where these components are in the engine compartment. I think they are all on the driver side mounted on on the wheel well.

Hi Danny, I was able to verify IGF voltage at 5 volts measured at the IGF connection point on the ignition harness. I went to measure the IGT, IGT2 and ICT3 and could not crank the engine. With the ignition switch on, battery voltage was dropping to 5 volts measured at the battery terminals. When the ignition was switched off, the voltage jumps back up. There seems to be a good short somewhere, maybe the key switch? I don’t think coils are a problem, the coil packs are only 3 or 4 months old.

Hi Danny, this car is with my son at college, so did not get to full troubleshooting until today. Looks like everything is good with the ECM. All measurements were taken on the Ignitor connector:
* While cranking IGT1, 2, 3 readings were jumping around. The highest reading I saw was 1.25V on a meter that updated about 2-3 times a second at terminal 5, 6 and 7. All three circuits behaved the same way in readout.
* IGF at terminal 4 was 5V and steady.
* I got battery voltage at terminal 2
* Also had battery voltage at terminals 1, 9 and 10

I explained on last update that something was draining the battery while the ignition switch was on, actually it is draining while the switch is off and key removed. Measured a steady 1A leak to ground. So the battery was very weak when I was seeing voltage drops with the ignition on last time. This time the battery was charged up, and I measured the leakage with everything off.

Cleared the p1300 code, and tried to start it several times. Is does start, but stops as soon as the key is taken off crank position. The p1300 came back, so it locks in immediately.

Not sure what the options are to test the ignitor. Are there any?

And, I got an electrical short somewhere, maybe independent of the ignition system issue?
*Maybe I start with the 15A fuse between battery and ignition switch to see if current draw goes away-that would indicate ignitions switch.
*Then pull 40A fuse to the starter relay to see if it goes away-that would indicate starter relay

I am also temped to buy an ignitor on eBay to see if the code goes away.

Any other suggestions are welcome for sure.

Thanks
Tim

Hi Danny, thanks. I will try replacing the ignitor and see if the car will start and run. It is a low cost option if the parts are used.

I still have the 1A going to ground issue when the car is off, key removed. Did you see those comments?

Hi guys, tried replacing the igniter module with a used one, and it did not help. The engine would still not start of the P1300 code was still there. Took it to a repair shop and the tech quickly diagnosed a ground on a connection to coil pack for cylinder 6. He replaced a frayed wire on that connection and all is good. Car runs well.

Hey, Danny,

I'm glad to know you.
Running a Turkchin Control means sliding blocker.
And I don't know how it works.
I hope you help me solve this problem Lexus GS 300 model 1998.

I want my Turkish to light up in the car.