03 escalade base model missing air ride compressor
 

ok so i got this escalade about 8 months ago from a dealership.. it was used.. but the error code wasnt on.. well when the system finally ran. the ride control light / error came on. well my mechanic been busy till now. he found time to take a look at it.. called caddilac and they said my year is a split model. so we dont know witch pump is what we need till we look and compare. well .. take the housing off.. il be dammed.. no compressor..
so now what.. is there any other way to find out witch compressor was in here...