ken2001

Hello forum
My car is a 2001 gs300.

My initial problem was a constant misfire code on cylinders 2 and 5 so I replaced the coil pack and kept getting the same code from time to time. The car would continue to run perfectly even when the check engine light would flash and then eventually stay on. I decided to did a little deeper by checking the electrical connections only to find frayed and exposed wiring on the electrical plug that feeds the coil pack. I removed them from the loom and then clipped them individually and then soldered fresh wire and new attachments.

My problem is now I keep getting a P1300 code and the car will only start momentarily then shut down. I probed the ignitor module and I do not have any positive voltage from C1 or C2 but C3 does have current. So I went to my local salvage yard and sourced on from another gs300 of the same year but I still have the same issue. A close friend of mine also has a GS300 so he allowed me to install my initial ignitor module into his car and it worked.
am looking at an ECU issue or is there a fuse or relay in the circuit that is preventing current?

Mr Jokster

iTrader: (8)

well its certainly not a module problem, you've proven that by swapping it into your friends car. According to the diagram, the igniter is powered through the main relay in the fuse box, pin 2 of the module. I dont see any fuses inline to it.

ken2001

Thanks for your reply....
My other question would be concerning the ignitor module.. There are several other wires.. they are ( C2-C3-GND-IGF-T3-T2-T1-TAC-+B-C1 )

I have a solid GROUND / The +B has current / and C1 has cureent when the ignition is on C2 and C3 do not..
TAC is the tachometer correct?

I'm not sure what the other leads are IGF / T3 / T2 / T1 ???

Mr Jokster

iTrader: (8)

ken2001

Thanks for all of your help.. I really appreciate it

vijayn

Did you get the problem sorted out?

Just reading your testing results, no coil should have current passing through it while ignition is on and engine is off. There should be 12V available on the terminals of C1, C2 and C3 on the igniter pack though.
If those results are correct, then it looks like a IGBT/MOSFET is blown inside the igniter pack as its shorted to ground instead of being triggered to ground by the ECU.

TW99GS300

I had the same symptoms around Feb just when a week long holiday began.
I had gutted my entire wiring, got a new igniter, and even cracked open my ECU to look for leaking capacitors.
Turned out, the cause of my problems were the wiring coming from the igniter going to the coil pack from exposure to heat.
1. I had recently had my timing belt and my valve cover seals replaced. The wiring harness was moved causing a crack leading to a short.
2. The coil pack pig tail was cracked and the pins were not connected in proper position.
I unwrapped all the wire shielding and found multiple places on the harness were shorting out. I replaced those wires and re-wrapped them with shrink wrap and wire loom.

Since the wiring position were inconsistent between the three coil packs I had switched them so they are the same. Meaning the common positive lead going to all 3 is on the top side of the coil pack harness while the separate ground lead is on the bottom of the harness when it is plugged into the coil pack. Some people has said polarity position has no affect but it had fixed my problem.

Edit: This is would be the same as what I was referring to with regards to position of the wire. https://www.clublexus.com/forums/gs-...or-wiring.html

This had happened to another GS owner local to me and plagued him for years. I did the exact same steps and fixed his problem as well.

I'd also recommend checking your coil packs to to see if they are within spec.
https://www.clublexus.com/forums/gs-...ml#post8303730

ken2001

Hello forum and thanks

My problem has been corrected.
I do not know exactly what the problem was... yesterday I just decided to remove the intake and remove the wiring from the loom altogether. I disconnected all the wiring from the ECU and used a spray can of electrical contact cleaner to spray everything and then used compressed air to blow the contacts as well. I also used heat shrink to protect several wires that had some cracking in them..

Ultimately a new wiring harness is in order because there are other pigtails and connecting plugs that are brittle...