s13 ca18det FP1 launch control switch input

[_KeRNeL_]

Hello,

I have updated my old base nistune to a FP1 board (44F0F) and I tested the launch control feature sucessfully based on speed trigger.

Now I want to be able to free rev in neutral/standstill, and also have launch control on demand, so I should wire the trigger line, but I have a question:

When I read the FP hardware install documentation I find refferences to use the steering power line as an input to trigger LC on and off, but then I found another comment about using the MAF calibration line in S13 CA18 (pin37 for non cat).

Which one would apply to my car (EDM S13 CA18DET 44F07)? I can't find anywhere in the software to choose the type of input, only the "launch switch" option in FP Flags.

may be I should assume that each boards firmware will automatically use the available input for its ECU, which In my case if I'm right it is the MAF CAL line (pin37), but then it raises another question: Will I have any impact in my MAF calibration by removing this input as my car is Non CAT (4 wire maf)

Thank you!

[_KeRNeL_]

I also have another two simple questions:

- why can't you use neutral switch which is already present? I.E.: when in neutral free rev, when in gear but < 16kmh LC on, when in gear > 16kmh free rev

- the switch should be push type or on/off? (I have FP1, not FP1.1)

[Matt]

We didn't want to accidently activate/deactivate for each gear change with neutral switch (for example if no speed input working, or if not wanted). So other switch was added (it was difficult to get working too)

FP1 is push on/push off. I updated that in FP1.1 to temporary push on, as that worked better

[_KeRNeL_]

thank you! I got it working perfectly with the maf input line.

do yo know if it affects anything to the air fuel mixture? otherwise...... why does the 4th maf wire even exist, if it is not used at all...

[Matt]

It's been a long time since I've done the code for this, but there was a MAF calibration input, which was hard set at the MAF. So we were able to reuse this line without affecting the MAF otherwise

[_KeRNeL_]

Hello.

I had my board updated to 44f0h (fp 1.1) and now the LC is activated with a temporary push button. The problem I have is that LC is activated constantly unless I cut the MAF calibration wire (pin 37) but this leads to no control over my idle mixture without updating the tune.

Is there a way to have both?

Idle mixture sends constant signal in the range 0-6v to pin 37

LC button sends temporary 12v to pin 37

It should be possible to have then both working independently at the same time

[Matt]

I've checked the code and we changed the MAF calibration, but I'll have to investigate further if that is tied to the switch (it isn't for EDM and JDM models, but the 44Fxx model does)

Are you saying if you adjust the MAF screw it is affecting mixtures at idle?

Code: Select all

rem Adjust MAF TP calibration from 12V to 5V
rem AE45 : B6 10 03 		ldaa	RAM_1003_AD_TP_Calib_OffsetB
rem AE48 : C6 AF 		ldab	#$AF => ldab $F0

[_KeRNeL_]

44fxx is EDM ca18det non cat version.

Maf signal works fine in the oem 44F07 ecu with old nistune (no fp) , if I adjust the maf screw the signal to the pin 37 varies from 0 to 6v and the mixture responds accordingly (showing in the afr meter values from 11:1 when 0v to 18:1 when 6v)

With the other ecu that I have (which has nistune board fp1.1 44F0H) the screw does not make any difference in the mixture (it sets afr as if the screw was in the middle all the time, nor adding fuel or substracting). I understand that this is overridden by the launch logic (temporary switch that sends 12v to pin37)

The problem is not only that I lost any idle adjustment, but I also had to depin the wire from the maf calibration to pin 37 on the ecu to force 0v when I dont want LC to be active, as any voltage greater than 0.5v is taken as LC on. It doesnt matter if it is 1v or 10v

I have a 10k ohm resistor to ground in the signal as the manual says, but makes no difference

[Matt]

The problem is not only that I lost any idle adjustment, but I also had to depin the wire from the maf calibration to pin 37 on the ecu to force 0v when I dont want LC to be active, as any voltage greater than 0.5v is taken as LC on. It doesnt matter if it is 1v or 10v. I have a 10k ohm resistor to ground in the signal as the manual says, but makes no difference

Okay so that is set hard coded for idle control. You should be able to adjust K/latency to compensate(to avoid firmware updates)

With regards to the wiring, the MAF calibration line when doing the LC wiring, this line needs to be cut (not spliced) and then wired to the switch. If you have splice, then you have both the MAF and switch connected which causes the issue as you noted