The other day (-5F) I started my truck normally, started driving down the road and I noticed the grid heaters were still on. I was going 40MPH (they are supposed to kick off at 15MPH) so I shut the engine down (while moving) and restarted it. The engine cycled fine, grid heaters came on then cycled off. The whole time I was still moving. Has not done it since.

Should I replace the relay as a preventative measure?

Any thoughts?

 

Try cleaning your IAT sensor first.
If you need to replace the relays skip the dealer and use Ford starter relays instead. At any auto parts for less than $10 each.

 

Thanks Bill!

 

Great tip Bill.....I imagine Cummins wants a small fortune for them...