If you convert from Air bags to Coil springs do you still need these air ride sensors? Since, its states air ride I would think not but I was told I still do. Does anyone know if this is correct or not?

 

Not needed. You will get a “Service air suspension” notice on your dash if you leave the air suspension in. There is a bypass you can wire in to not get that. I’ve also attached a pic I took of what another member did to keep his on board air. I’m going to try this method to see if I can keep the on board air.

 

What will happen if I just take this part completely off, with the coil spring conversion? I will still be able to use the compressor for tire inflation, right? The mechanic put a new one of these on my H2 because I got the code C0626. LEFT REAR POSITION SENSOR CIRCUIT PERFORMANCE. But if I am converting I wanted to see if they could return it, if I don't need it and get back what I paid for, about 100 bucks more then ordering it online. Also, on your attach pic, on the Fifth number. You lose the rear height adjustment feature when you convert to coil springs, anyhow, correct? The way it's worded sounds like you still have that feature. How, if its coil springs and not air bags?

 

Yes you can take it off and return it. The only reason to leave any of the air compressor stuff on is if the compressor that is used for your on board air is still working. In that case you would need to close loop the system and cap it off where the air bags were.

That pic of the post was not mine. Just something I saved. With coils the suspension leveling button will not work at all. No problem for me as I only ever used it to level out when the air system started failing any ways.

The FabTech coil springs I Put on are very heavy duty. Not worried about sagging at all as I’ll never tow with the Hummer anyways.

 

A couple of things. On that image above, it will not think that the ride height is always perfect. This only way that would be possible is if you were to physically remove the ride height sensors and in some way lock them in the exact position that the air ride computer thinks is "perfect". Otherwise any load in the rear and it will try to run the compressor forever until the sensors get back to the "perfect" ride height. In other words if you were to hook a rather tongue heavy trailer up the rear end is going to go down, the sensors will detect this drop and turn the compressor on until it raises back up to what it thinks is the normal height so the compressor will just run until it burns itself out or the load is removed from the hitch.

Additionally, if the compressor is left connected I'd also recommend physically unplugging the ride height switch (get a blank plate to replace it even) as pressing that will cause the same issue as above. When you press that button it knows a set voltage that the ride height sensors should increase by and will run the compressor until the ride height increases by about 2 inches which will never happen.

So my point is, yes the compressor can be left in place for the inflator function (not sure if carrying an extra 50lbs of weight around all the time is worth it just for that - in the long run that weight does use additional fuel) by dead heading it in the manner described but I'd strongly suggest getting ahold of a Tech2 so you can note the "perfect" ride height sensor voltages, then physically remove the sensor link bars from the arms and finding some way to lock the sensor arms in the exact right position and in some way disabling the ride height button.

 

In addition to the above by MixManSC the Air Suspension Control module also monitors the combined Ride-Height Sensors current (approx 10mA per sensor) and can also turn them off to save battery consumption.

The module can detect disconnected or shorted sensors, but I cannot confirm what error codes these generate.