g4x trigger setup problem

Hello everyone.

I am having trouble setting up my trigger setup. I have a nissan 240sx s14 with a ka24det. I have converted the distributor to a cas system with 24-1 tooth disk and the same ckp sensor in the bell housing. I made the harness and pinned trigger 1 for the crank and trigger 2 for cam. I tried using the nissan opto setting in the trigger setup but cannot see any crank or cam signal. Also tried multi tooth setting but noticed it detects a 24-1 tooth setting in trigger 1. I am unable to find that setting in trigger 2 since I wired trigger 2 for my camshaft signal.

Jacob,

The Nissan 360 opto setup is designed for a factory CAS with stock trigger disc inside which has a different tooth count than a 24 - 1 disc.

Trigger 1 is for your crank trigger so if you've fitted a 24 - 1 disc for that, you'd set Trigger 1 up for multi tooth missing, 24 teeth, 1 missing.

Trigger 2 is for cam sync so you wouldn't set that to look for the crank trigger disc pattern. I'm not clear what you have installed for cam sync. If you aren't certain either, I suggest using the trigger scope function to record cranking the vehicle, and see what your trigger 2 wire is receiving, in relation to the 24 - 1 received by trigger 1. For example, if trigger 2 shows one tooth each time trigger one completes a 24 - 1 cycle, then trigger 2 is a single tooth.

I hope that helps you narrow things down!

@Mike McGinnis

Thanks mike for the input. Performed the firware update. I ended up switching the the wires around for my crank and cam signals. Set trigger setup to multi tooth and put trigger 1 as my cam trigger and trigger 2 as my crank. After switching I was able to set trigger 1 as cam with the 24-1 disc setting. trigger 2 is reluctor setting for my crank. I was able to see a signal after that.

That scope looks very wrong to me and you havent really explained your set up very well. Is the CAS disc really a 24-1 or is it the more common 24 slot disc with a single sync slot?

The crank sensor must be connected to trigger 1, the cam sensor must be connected to trigger 2. Your cam sensor should output a single pulse per cam rev if the crank wheel has no missing tooth or other unique feature.

In your scope the cam sensor isnt even working, that is just 0.2V of "noise". Possibly the pull-up is not enabled.

Note you will get much quicker help on the Link forum, I only pop in here for an occasional look.

@ Adam@Link_ECU

Thanks adam for the reply. I'm new to making wire harnesses. But I have a aem 24-1 slot disc that i replaced in my distributor to make it a CAS. I recently just put a new battery and rechecked my trigger scope and noticed that there is no signal. I also noticed that I lose communication once I activate the starter from my switch panel. If I unplug the starter s terminal I dont lose signal when the starter button is activated, there are no glitches with my guages or communication to PcLink. So I figure that PcLink will never pick up a trigger signal cause it keeps loosing connection. I also have my power ground wires from standalone separate one on the block and the other on the head. Then a ground cable from the block to the chassis if that helps.

AEM dont make a 24-1 disc so I assume you actually have the 24 + 1 sync disc.

Do you have:

24T + 1 sync:

24-1:

The ECU disconnecting during cranking suggests you have a wiring issue, the G4X will stay alive down to about 6.0V so it is either losing the main power supply or you have a bad ground or something. It was obviously working earlier because the trigger scope in your first post shows the crank signal. Is it a plug-in ECU or wire in?

@ Adam@link_ecu

My setup is a link g4x storm wire-in. 24+1 CAS disc and a nissan ckp sensor in factory location on the bell housing. I cleaned up all ground locations and have not had a ecu dropout yet. Verified my trigger 1 pin is the ckp. Under trigger mode I set it to multi-tooth and tried to set the trigger 1 setting to reluctor and I'm lost at the tooth count but unsure if I setting it up right.

"Verified my trigger 1 pin is the ckp."

So did you change the wiring since your last scope capture?, as that showed the crank sensor was wired to trig 2.

Can you do a new scope and attach a copy of that and a copy of your tune. Put them inside a zip folder if the forum doesnt let you attach the native files.

@ Adam@linkEcu

Yes I did change my wires back so that crank sensor is on trigger 1. I think I setup my trigger1 setting right. Trigger 2 needs to be set right as I am unsure. I attached some images of the trigger scope and settings. I'm still new at using PcLink so I couldnt figure out all the logging at the moment.

The pull-up needs to be turned on on trigger 2.

Thanks Adam!

@ Adam@LinkEcu

After turning on the pull up on trigger 2 and sync the cam signal to cam pulse 1x this is the signal I get. Also noticed that I get no rpm signal and ignition says inactive. Should I see a rpm signal from these 2 triggers or is that a separate input that I need to modify into my harness.

Your scope shows only about 10 crank teeth per cam tooth which doesnt seem right for a crank trigger. Can you confirm how many teeth the crank wheel has.

@ Adam @LinkEcu

My crank sensor runs off my flywheel I would have to remove my trans or starter to properly count it. This was the problem when I was trying to setup the trigger setting. My distributor is converted with a 24+1 disc and I'm using honda k series ignition cop.

So does the flywheel have teeth/windows cut into it for the sensor or is it using the starter ring gear teeth?

starter ring gear

Yeah that isnt going to work. I would say what your scope is showing is trigger 2 is wired to the sensor which looks at the 24 slots, not the single sync slot. So the 10 crank teeth per trigger 2 tooth we see on the scope would work out to around 120 teeth on the crank which is about the ballpark for a ring gear.

The problem with this is for a "multitooth" trigger system to work, your "sync edge" needs to occur roughly centred between the same two crank teeth every revolution. However, assuming you have say 120 crank teeth, that is only 3 deg between crank teeth, when your sync sensor in the CAS which is loosely coupled to the crankshaft via a spiral gear drive and timing chain with large amounts of backlash and stretch, there is no way the sync will ever occur reliably between the same two crank teeth.

As a general rule, for a separate cam and crank sensor, about 24T is the max you can use for a multitooth trigger system.

The flywheel sensor on your engine would never have been designed or used for triggering, it would have been used only for misfire detection for emissions legislation. There is no way to make that work.

Your choices would be to put the wiring back to original and use the stock 360 slot disc or the 24 slot disc, or fit an aftermarket crank wheel with a more suitable tooth count - I would suggest a missing tooth type wheel such as 24-1 in that case.

@ Adam@link_ecu

Thanks adam for the help. I have done some research and looks like there are some flaws in my harness design. I will be redoing my harness and trying out the 360 disc and using the nissan opto 360 setting. Thanks again for the help.

@ Adam @ Link_Ecu

Rewired my CAS. Used the original disc and put my trigger setting to nissan opto 360. Disconnected the crank sensor on the bell housing. The problem I'm having is that there is no rpm signal and the ignition stays inactive. Is there something else that I am missing.

Your trigger scope now shows trigger 2 is still connected to the crank sensor somehow - except it is now offset by 4V. So I think that means you have moved the ground wire instead of the signal wire?

And you still have trig 1 and trig 2 swapped. Trigger 1 should be the "1deg" signal (360slots) and trig 2 should be the 180deg signal (4 slots).

Wiring should be like this:

@ Adam@Ecu_LinkEcu

The connector I have is a 6 pin one from a newer style distributor I believe. I"m only utilizing the sensor part cause I wanted to run k-series coils. Only using pins 3-6.

Pin 6 ground

Pin 5 12v power

pin 4 360 slot as trigger 1

pin 3: 4 slot as trigger 2

New trigger scope capture is attached below. The original crank sensor in the back of the engine is still disconnected. There still is no rpm signal and ignition still shows as inactive. Should I be seeing a rpm signal or do I need to wire in the rear sensor as a rpm input? Is there a baseline tooth count if I have to wire in the rear sensor.

Why is there an offset for the crank trigger signal? Is there a pullup resistor enabled? That should be disabled for VR (Variable Reluctance) / Magnetic-type sensors.

Or are you connected between 5V and Signal instead of Signal and Ground.

@ david ferguson

I am new to wiring harness building and tuning so bare with me,this is my first build. I believe the distro is a optical/hall effect sensor. The two signals are only in distributor. These are the settings I have.

I also have a crank sensor on the top of transmission bell housing but I was told its not a reliable crank sensor because it runs off a starter ring gear.

Your pinout for the distributor pins 3-6 is correct, and you are correct that this is all you need connected for a trigger. But is obviously not wired like you believe it is. The trigger scope still clearly shows the signal from the flywheel sensor on the trigger 1 trace.

So somehow you have still got the flywheel sensor connected to trigger 1. I suggest you unplug that flywheel sensor to make diagnosis easier and start by confirming there is continuity from pin 4 in the CAS plug to pin A8 in the storm plug, and continuity from CAS plug pin 6 to ECU pin A7.

@ Adam@Link_Ecu

Did some testing and found that its most likely bad harness design or wiring. Ended up bypassing the entire harness and spun the distributor by hand. I was able to get rpm signal , ignition became active on all 4 drivers, and looks like I got a cleaner trigger scope pattern.