Peterbilt SmartAir system

Good to know.
It looks like this (on the left side of the battery box). Maybe it will help you one day when you will see the same customisation)

 

AHH- I see now. Your first photo of the relay is upside down from the bottom.

Didn't recognize the photo.

 

Does anyone know if the SmartAir should run off of shore power without draining the batteries? I believe my batts are bad and need replacement. I’ve tried running it with shore power and it still drains them fast and then then take for ever to recharge.

 

No the system does not run directly off shore power. The system operates exclusively on 12vdc.

 

Yep, the ac runs off the batteries and shore service runs the charger. So bad batteries or corroded connections would cause issues keeping up.

 

So, my SmartAir system with AutoStart, only gets maybe like 2 Hours of use, on low fan @ 72 degrees, before it starts my truck to recharge. WHAT ARE AN AFFORDABLE alternative i can replace with in your opinion.

 

So on my truck with the Idle Free battery apu, the shore charger says 950 watt draw. I decided to see if my quiet little 2,000 watt Honda generator would run it. It does. So I went ahead and replaced the very old and non fixable agm batteries with the cheapest deep cycle floodeds I could find. Works like a champ. I'd bet you could buy the dual fuel model of that generator and whichever tank of your choice, for less than just the labor to modify your battery box to accept lithium batteries. But it does require a second fuel source etc., etc.
Otherwise, I don't think the word affordable will enter the equation.