I recently had to have my pcm replaced (twice, it's been in the shop for 3 MONTHS, two dealers refused to look at it, the symptoms were wacky) Anyhow, I've got it back and all seems well except the rear hvac blows neither hot/cold now. The front is fine. It has hot/cold hoses going in and the out is room temp. It has three relays in the rear and all test good. Is this coincidence or is there something related to the pcm? If it's not the pcm is there an actuator of some kind?