PCM Diagnostics & Tuning - Installed Lc1 as narrowband not switching??

I installed my Lc1 as the passenger side narrowband on my Z06. It doesnt through any codes but it also doesnt switch like the drivers side stock narrowband? Do I have a config setting wrong. I just used the defaut Innovate setup and didnt even hook up to the serial unit. The wideband works great, Im just wondering if the NB output is suppossed to switch. If not will it pass emissions? As I said its not throwing any codes for the O2s... :confused:

If it's not switching, it'll throw your LTFT's out of wack....happened to me. How exactly did you wire it up? Did you try slowing down the rate it reports voltage with the Innovate software?

If it's not switching, it'll throw your LTFT's out of wack....happened to me. How exactly did you wire it up? Did you try slowing down the rate it reports voltage with the Innovate software?

No I never even hooked up to the serial port, just left everthing as is....You think its switching too fast for the Pcm? LTFTs agree on both banks....and it isnt throwing a code?:confused: On another note damn it ran smooth in SD mode...but if I let it idle down too much it would occasionally go into reduced power mode...Any clues for that one as well? lol

My LC-1 has the same issue at idle with the output speed set at 1/12 and 1/6.

The LC1 won't switch on it own. Only when the pcm changes the fueling will it switch from one side to the other as it trys to maintain stoich.

Mine didnt switch initially, I could see the oem one working. Turned out my wiring was messed up. The 12v and Earth is easy, but the other 2 were like 4.8v each. So swapped them around and it worked fine.
Id double check your wiring.

Mine didnt switch initially, I could see the oem one working. Turned out my wiring was messed up. The 12v and Earth is easy, but the other 2 were like 4.8v each. So swapped them around and it worked fine.
Id double check your wiring.

well the wideband analog out is working very well and readng accurately. The narrowband simulation analog out is reading about .400 volts and it does appear to vary up and down with the mixture (varies between about .35 to .5 as the mixture changes) , it just doesnt switch as high and low as the stocker. Are you saying I have the Gm narrowband high and low inputs to the PCM swapped? I have the low grounded to the same chassis ground as the wideband analog out and the other (GMhigh) connected to the analog out 1 of the Lc1. If I had them swapped wouldnt I be seeing 0V?

A quick way to check the operation of the simulated NB on the LC-1 is to set the output range of AnalogOut1 to the same value. For example set the range hi/low to .3 or .75 volts. You'll then be able to read this with HPT as the O2 signal. This will force the a consistant output.

This is done via the LM programmer that comes with the LC-1.

A quick way to check the operation of the simulated NB on the LC-1 is to set the output range of AnalogOut1 to the same value. For example set the range hi/low to .3 or .75 volts. You'll then be able to read this with HPT as the O2 signal. This will force the a consistant output.

This is done via the LM programmer that comes with the LC-1.


Hmm I may have to hook up to it and play with the settings. Is the Lc1 narrowband sim suppossed to switch exactly like the stocker or is it just a low ranged version of the wideband output? Like I said my settings in the Lc1 are still exactly as it came from Innovate.

Thanks for all the responses guys, I really cant fathom why Im not throwing a code for insufficent switching.

The NB sim is a bit slower to start, but once hot it should swtich pretty much the same.
I think mine was stuck on like 0.400mv initially, and yes I meant NB sim output to pcm.
My WB was fine, NB was wrong. My earth is common with the rest too.

I have the low grounded to the same chassis ground as the wideband analog out and the other (GMhigh) connected to the analog out 1 of the Lc1.
At the NBO2 connector, connect the hi and lo signals directly to the LC-1, avoid connecting to any ground.

The wideband analog ground is not a "ground" and does not need to be grounded;
it goes to the analog "lo" of the logging interface and to the lo of the NBO2 connector.

Try like this and see if there's any difference.

Set the LC-1 narrowband sim to the default settings or to 0.0V=15.0AFR and 1.0V=14.3AFR (i.e. steep stepped graph approximately centered on 14.63AFR).

At the NBO2 connector, connect the hi and lo signals directly to the LC-1, avoid connecting to any ground.

The wideband analog ground is not a "ground" and does not need to be grounded;
it goes to the analog "lo" of the logging interface and to the lo of the NBO2 connector.

Try like this and see if there's any difference.

I followed soundengineers diagram which states chassis ground. If its the PCM ground or a good chassis ground the potential should be zero....It shouldnt make a bit of difference.

The NB sim is a bit slower to start, but once hot it should swtich pretty much the same.
I think mine was stuck on like 0.400mv initially, and yes I meant NB sim output to pcm.
My WB was fine, NB was wrong. My earth is common with the rest too.

So you simply reversed the two wires on the narrowband connector and it worked?? Mine appears also stuck at about .400 mV.

Can anyone post a direct connection to the stock PCM???

Pin A - ??
Pin B - ??
Pin C - ??
Pin D - ??

Thanks

A = NBO2 Signal Low = LC-1 green
B = NBO2 Signal High = LC-1 yellow
C = Heater Ground = LC-1 blue
D = Heater Power = LC-1 red