gabrielsousa

i have same doubts about where to wire the lc-1 ground

where can i wire the ground ?

VegasInvasion

I use A23 for all the grounds, and A25 for power. They're right next to each other and it's switched, can't go wrong.
The brown wideband wire works better on D14 for me. But you're defeating the benefit of the LC1 if you're not using direct serial logging with Neptune.

gabrielsousa

D14 is limited to 3.8v .

what are the benefits of direct serial logging ?

gabrielsousa

and the BLACK ( calibration ) on A23 too ?

gabrielsousa

old connections

A25 -> RED
D10 -> BROWN
D22 -> BLUE and WHITE
A23 -> BLACK
LC-1 offset is -0.18

---------------------------------------------

now my connections

A25 -> RED
D10 -> BROWN
D22 -> WHITE
A23 -> BLUE and BLACK
LC-1 offset is ZERO :D

VegasInvasion

I would suggest using the same node for all grounds to avoid interference.
There is virtually no reason to ever need an AFR leaner than 3.8v, so unless you're doing a hypermileage tune, use D14.

gabrielsousa

thanks a lot.

i have a old firemware, if i upate the LC-1 firmware do i need to recalibrate ?

gabrielsousa

i change the LC-1 ground from D22 to A23 ,
and now shows less 2.0 AFR (ex. when was 15.0 is now 17.0)

but i if i change back the ground from A23 to D22
i have back my old AFR

when we change the ground do we need to calibrate again ?

i have more 30% fuel comparing to sotck p30, and a 70% duty cycle, i think the 2.0 less AFR isnt right

LTCxD2B

The ground should be at the chassis not an Ecu wire

gabrielsousa

like this

LTCxD2B

Yes

gabrielsousa

i was reading the AFR on neptune and tunerview ,
i connected the LC-1 on pc and with LogWorks, and the AFR is the same when the ground in on A23/A24 and the same on D22 , theres no change in AFR independently the ground source i use

the strange thing is, with different ground sources changes the AFR value on D10 /D14 (neptune) , but not on LogWorks
so...
using the D22 ground i have the same AFR value on neptune that shows on LogWorks ,
using A23/A24 ground i have less 2.0 AFR on neptune that shows on LogWorks

gabrielsousa

i had a -0.18 offset with BLUE (heater ground) and WHITE (system ground) on D22

with the WHITE (system ground) on D22
i change only the BLUE (heater ground) to A23, and now i have the same on LogWorks with ZERO offset

A25 -> RED
D10 -> BROWN
D22 -> WHITE
A23 -> BLUE and BLACK


now my LC-1 offset is ZERO :D

gabrielsousa

is the A26 ground better than A23 ground to connect the LC1 ground ?

Txdragon

Since I am searching for some info and found this post particularly, I will update it since it has fallen into limbo.. Short answer is the voltage output of the sensor is referenced to the ground. If the device measuring the sensor is connected to a different ground, the voltage difference between the grounds can shift the sensor output voltage relative to the measuring device. Yes, you should recalibrate if you change grounds.