i have megasquirt pnp installed on a 91 1.6. i also have a lc1 with db blue hauge installed as well. my question is, th direction say to hook up the brown analog 2 wire to the blue wire on the gauge. the brown analog 2 wire is 0-5 v the yellow analog 1 wire is something different. my question is can i go ahead and splice my stock o2 single wire into the same brown circuit or will it overload the circuit. i tried to connect the lc-1 to my laptop but it says that it does not recognize the sensor. im looking for an easy way out and wanted to know if this will work.



thanks,
\dave

 

anyone got any ideas? or can someone guide me to why my laptop wont connect to my lc1? i used a serial to usb adapter that i used for my megasquirt no problems.

 

first thing to check is make sure you have at least 12.5 volts going to the unit. they are very finicky for voltage. second thing is make sure you have the most current firmware from innovate.

when you say connect to your lap top are you talking about in megatune, or in log works? if in logworks the only way I could get it to work was if the voltage was spot on and you had the unit powered up before opening logworks. if I had log works open and then powered the unit up I could never get it to connect.

if you are talking about seeing the readings in megatune, then there are some other things you need to check. make sure you are using pin 10 in the center harness. don't go by the tiny numbers printed on the plug cause they aren't right. count the wires starting from the top left. In that center plug there are two wires that have voltage one has 12v and one puts out 5v. grab a volt meter and find the 5 volt wire and use it to test the wire you think is pin 10. (I stole this from Joe) you should see your a/f ratio jump to full lean in megatune if you have the right one. you also need to check that you actualy have signal coming from the brown wire. my second LC-1 wouldn't put out any signal no matter what I did.

if all this fails and you have everything set up properly in megatune you can allways do what I did and take it out in the yard grab, "Elvis"(my beloved .357 magnum) or equivelent ,shoot that somebitch and the resort to buying an AEM uego thats works perfectly out of the box.

 

i was referring to it not connecting to lm programmer to change the yellow analog wire from the weird voltage output it has to 0-5v output using tlm programmer to do so

 

There's a fairly good chance you can split the brown wire's signal, but using the yellow wire would be a better option. You might want to put a 470 ohm resistor in line with the wire leading to the Megasquirt if you try signal splitting.

 

I currently have the brown wire directly split into a gauge and the MS. So far, I do not see any problems and the gauge and MS see the same number.

 

Any issues with interference from running the wires so close together? MegaTune and the DB gauge have the same settings on the lc-1, but different readings.

Any thoughts?

 

There shouldn't be any "crosstalk" issues. I suspect you have a ground offset issue.

 

does it read differently if you pull the wire from one or the other?

 

i havent soldered the wire to it as i was afraid that i would short something out or mess up the lc-1

 

Just checked it today while warming up the car. Idle was at 12.2-12.6. Once i removed the wire to the MS, the idle stayed at 12.2-12.5.

 

I thought the brown wire was 0-5 volts from the factory and the analog 1 wire was 0-1 volts from the factory. I plan to reprogram the LC-1 to make them both the same--is this not possible? I plan to install the LC-1 this week. Have I missed something here?

 

This is correct. As delivered, the yellow wire (analog 1) is a non-linear 0-1v scale which emulates a narrowband sensor, and the brown wire (analog 2) is a linear 0-5v output. Both outputs can be re-programmed to any calibration which you desire.

Did something in this thread lead you to believe otherwise?

 

I just did not understand the reason for splitting the brown wire signal vs. using a reprogrammed yellow wire signal. I plan to route the brown wire to the MSPNP and the yellow wire to my gauge. Hopefully, I can reconfigure the yellow wire to read a proper AFR.