2 Step RPM Limter Acting While Driving, NDS Flag issue?

[ThatGuy]

I'm familiarizing myself with the tools (Quaterhorse and TunerPro RT) before I start making meaningful modifications to my engine. Right now I have a 1989 F-250 351 Windsor with a S5-42 manual transmission, A9L converted with SEFI, MAF, 2 HEGOs, 3" exhaust w/ shorty headers w/ EGR, 24lb/hr accel injectors, BBK calibrated MAF, no cats, and otherwise stock.

I applied the A9L2 base tune, have the GUFX_210129 definition file, and the Decipha_210225 ADX file. I then modified the base tune based upon the write ups to reflect my injector information, MAF curve, etc. I did my first hard pull in 2nd gear, and ran in to the rev limiter at around 4800rpm. Did some digging, it appears to be the same RPM as the the two step rev limiter value. I was moving and at WOT during this event, and I'm not sure why this kicked in.

Doing some more digging, I found that the NDS flag was reading as neutral. Watching the whole log, it appears that the NDS responds in reverse of what it should. Electrically everything appears in order (neutral=0vdc on pin 30, gear=greater than 4.5vdc on pin 30), so I am wondering if there is a corruption somewhere, or if I goofed something?

[decipha]

theres a patch to reverse the 2 step as some people for some reason have an inverted input

[ThatGuy]

Thanks for the response! I've taken a look, but can't seem to find a patch that modifies the input. Since I don't need the 2 step rev limiter at this time, I can remove the patch (Z_XTWO_STEP), but wouldn't the inverted input cause me to look at incorrect values in some other parameters?

[decipha]

viewtopic.php?p=4640

[ThatGuy]

Awesome, thank you! I really appreciate it, and the write ups too.

[decipha]

no prob

[drewloch]

I know this is an older thread, but I am seeing similar behavior with the NDS flag. I too am just getting started and want to ensure all my sensor inputs are operating correctly before progressing further.

I have an A9L computer with a C4 transmission. Only change to configuration so far is to modify TRLOAD = 4 (auto, non-electronic, neutral safety switch).
I am running the latest versions of the configuration (GUFX_230909.xdf, A9L2_231024.bin, DECIPHA_230417.adx)

Using the dash, I am seeing that when the transmission is in park or neutral that the NDS Flag monitoring shows Drive. If I depress the throttle it transitions to neutral. If I shift into Reverse or Drive it also transitions to neutral. The ECU pin is grounded when in park/neutral and open otherwise.

Am I supposed to enable or disable the 2-step code to get the inverted input? When the proper value is applied, will it be reflected correctly in the NDSFLG bitmask in the ADX or will I need to edit the definition and change Display to also invert the "Display on True" and "Display on False"?

Would appreciate any help/guidance, thanks!

[decipha]

You never need to edit the definition for anything just LMK when you see an error.

If you disable the 2-step code then you won't have any 2 step.

press f10 to pull up the comments of any patch you apply or remove.

with trload set to 4 you'll need to use the brake pedal for the 2 step code

[drewloch]

Thanks for the quick response.

At this point I am only worried about the NDS position being correctly identified by the tune and not necessarily the correct behavior of the 2-step code. If the auto trans shifter position is not important to the tune, then please let me know.

Here is what I did yesterday:
With the 2-step code in the default setting of patched, I modified the RunningState monitor to display the NDSFLAG.

With the trans in Park or Neutral, the NDS shows as "Drive" with my foot off the gas. If I tap the accelerator it switches to show no text. If I put the trans in Drive then the NDSFLG shows no text.

I believe I then correctly disabled the 2-step code and the NDSFLAG was still showing the same behavior with the same tests.

I am happy to try other tests or send logs if it is helpful. It may be another day or two before I am out there working on it again.