Hi all. No excuses. I'm a dope and opened the black cap on the AC line near the passenger side firewall (right beside my ATF filler tube). Ony for a couple seconds, but apparently long enough to let out all the AC juice. It hissed, I re-capped it, and next time I went for a drive - I sweated like crazy in the Florida heat. So I took it to my mechanic who rolled out an AC machine, undid the same cap, hooked up the machine, punched in some stuff and fired it off. After it shut off, we started the car - nothing. No cold air AT ALL. Now before I opened the cap - this Jag blew COLD! It was awesome! He saw my frustration (frustration with myself... and with this car have reached an all time high) and said to bring it back next week - give him an hour... that sometimes the motors get stuck? or something like that. Sorry - poor memory. But I am wondering if anyone here has any suggestions. I have begun reading through the different AC threads and none of them sounds like this - where it was working perfectly until I opened that little cap and now - nothing. Anyway, any thoughts, suggestions, or things I could try out today would sure be welcome.

 

That little cap is just a dust cover. There's a check valve there just like a tire valve. I think the self test is the same as for the XK8, and while it may not help, it's easy to do.

Another possibility is to do a hard reset: disconnect the negative battery cable and touch it to the positive post for about 15 sec. Then reconnect and turn key to power the systems up but wait 30 sec. before starting the engine. This allows the ECU to communicate with the other modules and revert to factory settings.

The idle will be unusually high at first, but will settle down .

 

hi and thanks for the reply! do I leave the positive cable connected or undo it before touching the negative to it? thanks

 

Your tech is probably going to draw a vacuum to clear the A/C system, this takes a while. He will then recharge it with freon.

 

just looked up hard reset and read up on it some more and found my answer! psyched to go try it. fingers crossed... and hopefully still attached afterward.

 

Good luck, but I am really wondering how a hard reset is going to work on your A/C. You might look up X308 A/C diagnostics and see if you have any codes.

 

First and foremost, if all you did was unscrew a dust cap and refrigerant leaked out, that Schrader valve needs replaced. At this age, they both need replaced.

I’m willing to bet that the A/C compressor didn’t come on even after injecting refrigerant. When I charge Freon into a system, I get a choice prompt on the service machine screen to inject it into the low side, high side or both ports, I always chose both ports. Every tech has their reasoning, this is just my method. My main reason to do both ports is primarily what I believe happened in your situation. If the tech injected Freon in the low side port only and the compressor didn’t kick on, I believe it’s because the high pressure switch didn’t see enough pressure in the system and never even bothered to command the compressor clutch relay to engage. I know this doesn’t help you now but, just to get a basic understanding.

 

Hmmm. Sadly, I have no idea. He told me to drop it off Monday and let him have an hour with it. I can ask him then. Is it too late? I did what the person above suggested and came up with codes 23, 41, 42, and 46. In brief - 23 "Refrigerant pressure switch malfunction. Refrigerant pressure low. Leak from damaged pipe or joint" - But it worked PERFECTLY until I opened that damn cap!

Code 41 - Left Hand Recirc motor Fault Harness/connector fault. Servo motor seized or stuck or sticking flap

Code 42 - Right Hand Recirc motor Fault Harness/ connector fault. Servo motor seized or sticking or sticking flap BOTH say refer to PDU

Code 46 - Foot vent motor fault harness/connector fault servo motor seized or sticking or sticking flap.

I also tried the Hard reset. No luck clearing those codes or getting the AC to miraculously begin working again.

Any insights or thoughts on what I can tinker on this weekend or take to the mechanic Monday? Thanks in advance

 

Take a look at the pressure switch: any green stuff leaking out (a blown switch)? No. Then let him recharge the system after drawing a vacuum. Those codes imply low pressure . . .

 

So I did a hard reset with just taking the negative off and touching it to the positive. That didn't seem to do anything. I drove around a bit hoping maybe the AC would wake up, came home, and parked. Decided to do it a second time - this time taking both battery cables off and touching them together for 15 seconds. Got back in and the ABS light/ traction control and Stabilizer light that was intermittantly coming on and going off (mechanic said something about a control module) went off completely and Jag seems to be braking better than ever. My question is - should I keep doing Hard Resets? Or when is enough enough? Also, I read a thread related to the codes I found when I did that AC code test. A guy said behind the driver's seat - in front of the back seat, is a fuse box and there are 2 relay switches - black. He replaced them and the codes went away AND his air blew cold again. I took mine out and drove without them and car was definately hotter... blew HOT florida air in. So obviously was getting some cooler air - just nowhere near what could be considered air conditioning. Still welcoming any opinions

 

That's enough hard reset. All it does is discharge capacitors and revert to factory settings. It does appear that the Schrader valve is either faulty or has dirt in it preventing proper seating.

 

If you want to touch the cables, whether you do it when one or when both cables are disconnected makes no difference. According to the Jaguar Service Training manual, touching the cables for 15 or whatever seconds is not the correct way. This is the correct procedure:

 

Wait... so follow the previous suggestion of touching cables with key "on" for 60 seconds... not 15? Same operation, just longer amount of time?

 

Sorry - "Draw a vacuum"? I'm sure he'll know what it means... but I don't. Is that to get any moisture?

 

I came up with codes 23, 41, 42, and 46. Found another post where someone swapped out 2 relays from fuse box behind driver's seat (By heals of left rear passengers feet) and AC problem and codes fixed.

 

As you can see, the procedure described in the Jag manual does not require any touching or having the key "on", just disconnect for 60 sec. and reconnect.

 

Code 23 basically means either low refrigerant or faulty pressure switch. In both cases, the AC compressor will not come on so get the system pressure checked and recharged if required first then go from there. The other codes will not prevent the AC from operating.

 

So not sure what is going on other than the distinct possibility this car is possessed... but late yesterday I took out the two black AC relays from behind the driver's seat (on the floor by the back seat rider's heels) and went to see if I could get a replacement a Oreillys. Not until Tuesday. So i left them out and drove home. Car was MUCH hotter - which led my addled brain to conclude at least SOME cooler air was getting through. Well, today I put those relays back in, made sure they were all snuggly seated, and for giggles fired up the jag. Though by no means cold, it seemed even a bit cooler. So I shut it off and checked the codes the way the video shows AGAIN. This time Code 41 dropped off "Left Hand fresh/Recirc. Motor Fault harness/connector fault Servo motor seized or sticking. Flap seized or sticking. Refer to PDU" Me thinks because I was in the driver's seat and this refers to LH (Left Hand) not RH - this is why it was noticeable. But christ... why, if at all, would removing those relays and reseating them clear a code? and if that is the reason - why not all? Or is something else going on and that happened to be a fluke? I'm telling you... this car, for a guy with a noggin like mine, is crazy making. I think I am about to sell it. Anyone want a Jag?

 

Update: Found a thread about how to clear AC codes (rear defrost and foot arrow buttons) and did. Now the only code flashing is "23" which makes sense if the young man at the garage only filled the tube by my ATF filler tube (still can't figure out if that is called the upper or lower tube). Anyway, thank you all. Will drop the car off at the garage tomorrow AM and mention it has 2 fill locations and go from there. Hopefully be back in cold air by midday.

 

UPDATE of UPDATE: Took to garage, he vacuumed it and filled both upper and lower. Blows as it should now! Thank god!