Thanks Sean, I found this thread https://www.jaguarforums.com/forum/x...no-heat-82567/ that has this explanation in post #7

I cleared the codes and will take a look at the grill/sensor later, right now I have to go to work!

Thanks again.

Mike

 

Well, this is what happened today -- I drove a short distance with AC on Auto and then all of a sudden it was on Manual! I hit Auto and a very short time it went back to Manual. Now it switches to Manual after a few seconds or maybe minutes. I checked the codes -- ZERO codes! I haven't checked the grill/sensor yet.

It almost seems to happen when I am braking, but I can't completely verify that. I tried pumping the brakes while sitting in PARK and after 7 pumps it went from Auto to Manual. Tried it again, couldn't get it to happen. Sat for a couple minutes in Park not pumping the brake and nothing happened. I did replace the Brake Pedal Position Switch recently -- don't know if that could have anything to do with it (doubtful, right?), but wanted to mention it here for completeness.

Any more ideas?

 

I took out the one screw that holds the change holder in and took it out -- but for the life of me I can't get the "grill" to pop out. I tried using a plastic putty knife to pry the bottom out but the top edge seems to be stuck. I don't want to break it, so thought it was best to come back here and ask if there's a "trick" to getting it out. Where are the clips or whatever holds it in? I can loosen the bottom, but when I try to get the top out, the bottom snaps back in place. Even with the bottom edge in place, I can't get the top edge to even budge a little. Almost feels like it's screwed in, but that's not my understanding.

Here's a photo of the grill -- hopefully I'm trying to remove the right piece!

 

I finally got my car back from the mechanic -- had to have the transmission rebuilt!

I've driven about 250 miles since I got it back and the AC has stayed on Auto the entire time. Just before the transmission failure, I couldn't keep it on Auto for more than a few seconds.

Is it "just one of those anomalies" or could the transmission failure have had something to do with the AC issue?

 

Maybe the mechanic had the battery disconnected for a long period of time while rebuilding the transmission, and it resolved the issue better than a hard reset would?

I don't know. Cars can be quite baffling at times. Especially British purring cars...

 

Two fer one ain't bad! Did the transmission repair also solve the vibration issue?

I am guessing the air bag light is still on(?)

 

The vibration seems to be almost gone -- could be my imagination, though!

The air bag light is still on.

 

That makes a lot of sense. If a dirty pot. were to change resistance the controller could interpret this as a command to change temp., fan speed, etc.
Perhaps a shot of contact cleaner into those controls would help.