If the LCM was fully refurbished and tested and you're still having these symptoms:
-
Interior lights still stay on all the time (won't turn off)
-
Turn signals not working
-
One or both headlights not working properly
Chances are there is something in the vehicle at fault. The harness that connects to the LCM uses crimp-on connectors. The conductors inside the wire jack corrode and break over time.
The multi-function switch on the steering wheel column is also wired in series with the headlight output of the LCM. If there is an issue with the harness or multi-function switch, the lighting may flicker intermittently or simply stay on.
You can use a voltmeter or lightbulb probe to quickly test the headlight output terminals on the LCM. If it's showing +12 volts at the LCM when the headlights are turned off, the issue is most likely not the LCM.
Also, for the interior lights to stay on all the time, there is a switch on the door jam that over time wears out and can't properly switch on or off. Testing and replacing this should help resolve the interior lights staying on.