I have a 2014 F150 that had a CNG system on it when I purchased it. I have removed the CNG tank and lines, which causes the Check Engine light to come on showing "Unable to communicate with alternative fuel source". Tried to have Ford Re-Flash the ECM but something in the electronics of the CNG system blocks them from being able to re-flash it. Tried multiple times to contact the CNG system manufacturer but have gotten no response.

Does anyone have any idea which wire in the wiring harness that plugs into the back of the instrument cluster feeds the Check Engine Light? At this point I just want to disconnect that wire to turn the light off. The truck has 300k on it and I plan to drive it until it drops, the light just drives me nuts.

Thanks if anyone can help.

 

Put a piece of black tape over it.

 

There isn't one, it doesn't work that way.