daytime and low beam headlights flickering/shutting off? freightliner 114/108sd

hi guys , new to the forum and have a few quick questions

i am a apprentice mechanic for a fleet of freightliner 114sd's which are all the same year 2013 ,
one of the trucks has a bad connection to the headlights every time he hits a bump they flicker or go out , both daytimes and low beams , now i have checked all of the grounds to the forward chassis harness , loose connections ect, the headlights run off the bulkhead module and chassis module , it happens very random and have not found any bad grounds or loose wiring , the bulkhead module is throwing a code BH 33 which i could find no info on , and sometimes the headlights would go out even with the truck off sitting there , im just not getting anywhere on this ,any ideas on what i could do next would be great ,

next thing im going to do is cut the grounds and run new ones to chassis if thats not it im thinking short in a positive somewhere or bulkhead module has something internnal loose?

 

thanks for the replies , i have yet to cut any wires , il be at work tomorrow again looking at it , the truck has a switch for low beams and marker lights on the dash and only a high beam on the column ,the brights do work and will always stay on without issues, as long as you switch them before the low beams or daylights flicker, i am pretty limited as far as diagnostic tools go and if we cant fix it , we have to send it in for repair

 

thanks for replying , yes both are going out at once , but i noticed there had been some wiring added to the left side connecting the right side , i had asked my boss about this and he say when it was only a few months old , the right side would go oiut over bumps and he sent it in , i guess this was there fix, green power wire from left headlight to right headlight? , when i switch the low beams on , and hit a bump they dont flicker they just go out completly and dont come back on until you turn the switchg on and off , if this happens high beams wont work because the low beam circut isnt energized , but if its working and you switch to high beams they stay on and do not flicker , neither do the marker lights ,

i looked at it today and the driver said no issues all day so i couldnt really diagnose anything today , even if it did stop , id still like to familiarize myself with this stuff as i have to work on 16 of the same by myself