i have a 99 24v 3500 and this morning i went to leave for work i let the truck warm up for ten min went to hit my lights and the truck shut off turn the lights off start the truck back up turn the lights on and the truck shuts back off i did it one more time and it was fine but when i was driving the abs light and check engine light were flashing came home after work and tried to turn the lights on and now i can get the truck to run at all with the head lights on im think it shorting some where but where? any ideas? please help! thank you!

 

check to make sure your battery connections, the power lead to the fuse box is real clean the light could be pulling power from the run circuit also all your grounds are clean and tight, then start hunting down a chaffed wire.

 

turned out it was ground g 102 wire under the distribution box was broke and couldn't carry enough load to hold both relays on at the same time

 

thanks for posting the problem/fix... helps others down the road