Wiring up an LC1
My WB is on its way and I dont want to do a half assed job wiring it into the car. I need to tap it for power somewhere.
1. I wanted to use an add a circuit. Except one problem, I never looked if I can put one in the miata. If I can, where would it go and if not then how do you recommend I wire it?
2. Does the gauge require a separate power source?
3. How do I send the signal to both the MS and the Gauge with one output while sending a signal to the factory ECU with the other? Just splice the WB output and thats it?
Thats all. My main concern is power for it. I want to know what I need for its installation so I can get it friday night and get up 8am saturday to get to work.
Thanks guys.
1. I wanted to use an add a circuit. Except one problem, I never looked if I can put one in the miata. If I can, where would it go and if not then how do you recommend I wire it?
2. Does the gauge require a separate power source?
3. How do I send the signal to both the MS and the Gauge with one output while sending a signal to the factory ECU with the other? Just splice the WB output and thats it?
Thats all. My main concern is power for it. I want to know what I need for its installation so I can get it friday night and get up 8am saturday to get to work.
Thanks guys.
Where can I connect the heater ground. I probably shouldnt put it on MS grounds, can I just attach it to the chassis next to the MS or do I have to run it back to the throttle body?
The 12v feed for my Bipes was tapped off the switched 12v feed to the stock ECU. When I sold my Bipes, I left 6" of that wire still tapped into the harness. I used it to power my LC1. For the ground, I used a 16g wire and ran it to the same ground point on the back of the engine block near the coils.
To do the initial free air calibration on the LC1, first unplug the controller from the sensor. Apply power to the LC1 for 20 seconds and then remove power. Connect the sensor... MUST NOT BE IN THE TAILPIPE! MUST BE EXPOSED TO AIR THAT CONTAINS NO FUEL FUMES! And then apply power to the LC1 for 2 minutes. Remove power. Done.
To test that the free-air calibration worked, just use the included LED light. Touch the led to the BLACK wire and to a ground point. If the led is solid (not blinking) after the 2 minutes, you're good. Connect the brown wire to your WBO2 input on your ECU and you should be good. LC1's can be finicky, but mine was just as easy as I described.
The bung on my Begi DP is on the RIGHT side of the pipe. I ran the wire up through the floor through the hole for the shifter, and then put a little notch in the lower shift boot so the wire wasn't crushed. The cable was just long enough that the LC1 rest nicely directly behind my radio inside the center console.
Except both outputs are completely & independandtly programmable. Also, the default 5V output settings are retarded.
^Really, mine is feeding my MS just fine. I tried to get the thing to hook up to my laptop but it wouldn't recognize my USB>Serial cable... but if I ever get it to recognize, what should I do to the settings?
5v = 20 afr
just like what megatune asks for.
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I got it in the car, its plugged in, i did the free air calibration. I mounted it under the hood as well.
I need to know one thing now and thats how do I connect it to the factory sensor? Its a four wire, two blacks, a blue and a white Or should I just leave it dangling?
edit: Mine isnt recognizing either. Damnit.
edit 2: Just used my computer to update the firmware. The new firmware automatically sets the above numbers.
Last edited by Saml01; Dec 1, 2007 at 01:13 PM.
Well its in the car, it works, megasquirt shows its reading. Now just to tune.
Had to redo free air calibration once, I hope that was a fluke occurrence.
I picked the wrong time of the year to do this, I was freeeezing. I didnt have enough energy to run the wires for the gauge even. But right now im more concerned with getting the car driveable for another month or two then I can park it for the winter and then pick this up in the spring.
edit: You guys should have seen me this morning.
I freaked out and wanted to turn back. Chad had to calm me down.
Had to redo free air calibration once, I hope that was a fluke occurrence.
I picked the wrong time of the year to do this, I was freeeezing. I didnt have enough energy to run the wires for the gauge even. But right now im more concerned with getting the car driveable for another month or two then I can park it for the winter and then pick this up in the spring.
edit: You guys should have seen me this morning.
I freaked out and wanted to turn back. Chad had to calm me down.
Last edited by Saml01; Dec 1, 2007 at 05:27 PM.
mine ate through sensors, always had to re-calibrate it, and could never get the second output to work, AFR would bounce like a narrow band really bad even after playing with the settings
The default (IIRC) is 7.3:1-22:1, which is great that the sensor has that type of range, but really anything richer than 10.5:1 or leaner than 19:1 is pretty much useless.
After you change the outputs in the LC, you have to update MegaTune in the Configurator. For now, make sure you're using the LC1 Default settings in Config.








