LM-1 Question

[Pulse_GTO]

What AFR range does the PID in the Scanner use for the LM-1? I know the unit has a range of ~7 to ~22. I use my own PID, but I was just curious.

[azfrc]

I calculated backwards from what their calculation was in the table.

LM1 voltage/.5 +10 = AFR



0 to 5 volts = 10 to 20%AFR

offset the AFR by 10

0 to 5 volts = 0 to 10%AFR (add the 10% back later)

now its a ratio of 5 volts to 10%AFR or 5/10 = .5


I know, I'd make a lousy algebra teacher

[blownbluez06]

Should actually be 10-18 0-5v (output/.625) +10

[JnJSpdShop]

Should actually be 10-18 0-5v (output/.625) +10

Isn't the LM-1 designed to output AFR from 10-20:1? Why are you suggesting 10-18 AFR?

[SkullV]

Most people who use the LM-1 with HPtuners have changed their LM-1 to output 10-18 AFR from what I understand. That's what I did and it works great.

[Phil'sC5Vette]

whats right?
I have one reading off the LM1
On off my PID
and one from my HPT

all three are differant

are my voltage numbers not consistent, if not what should they be so the reading from the LM1 ( which I assume is the right one) to match and work in my HPT

[jimmyblue]

It's my observation that the LM-1 transfer curve is
not to be assumed, make sure it agrees (in intent)
with the HPTuners PID you use. That means hitting
the serial bus via LMProgrammer, at least every time
you change out the 9V battery. Then you are down
to ground offset errors, and I've said my piece on
the right way to fix that (inconvenient perhaps, but
totally effective).

[SkullV]

It's my observation that the LM-1 transfer curve is
not to be assumed, make sure it agrees (in intent)
with the HPTuners PID you use. That means hitting
the serial bus via LMProgrammer, at least every time
you change out the 9V battery. Then you are down
to ground offset errors, and I've said my piece on
the right way to fix that (inconvenient perhaps, but
totally effective).

I have mine hardwired and only set the LM-1 with the serial port once, and have it hooked up to hptuners and since I created the pid the first time Hptuners ALWAYS matches the LM-1 screen.

[Phil'sC5Vette]

I read a ton of posts, but I need someone to make it simpler for me. I cant seem to get the same reading on my PID histo, LM1, and PID gauge.

I found and read alot of LC1 posts, but limited LM1 posts.

Im slow and im looking for a pictures verison with a set by step plan that shows what to do first ( HPT or LM1) and the process to do it. Ive found a couple close, but they seem to jump around.

[sunny]

How about clicking linear then Volts O.5 + 8 giving a range of 8-18. This puts 13 in the middle of the wideband voltage. Have no idea if that helps a thing but it matches the LM1 Screen output ever time.

I suppose .625 +9 might give more accuracy while also putting 13 at the center of the 5 volts. Again, scaling like this probably doesn’t help anything.

Be sure you have the green plug wired right.

[01SDime]

0 to 5 volts = 10 to 20%AFR

I'm getting ready to set up my LM-1 to plug into the HPTuners so I can read the A/F ratio on the scanner. Are those values what I setup on the LM Programmer?

Aka this:

So basically do I change those values from 0.883V to 0V and the 4.216V to 5V? I copied this image from Innovate's website which was instructing how to setup an LC-1 to EFILive, so thats where those original values come from. I'm completely new to hooking this stuff up so I've been trying to understand from this thread how everything works.

[JimMueller]

I actually set mine as 0v-5v=11AFR-17AFR, merely to get more resolution. I also set the update speed to 1/6s (I think I got this recommendation off the Innovate forum). These offset and slope errors are a pain in my rear.

Jimmy, what's your charge for calibrating my LM-1 if I drive over?

[01SDime]

Where do you set the update speed? Is that under the Advanced button?

[sunny]

Yes under advanced