A/C help please

[CMV]

Fighting with my A/C system. Maybe from the symptoms/observations you guys can give me some direction of what to try next?

The dash info panel says "service ac system".

I get code B1341 which is Air Mix Door Two Movement Fault. This code will not clear with a high-end Soleus nor the on dash code display/reading/clearing methods.

The compressor will not start - assuming the trouble code is preventing it from starting, but I've read of others with general one side hot, one side cold that get the same code and their compressors do kick on.

On the HVAC control panel it reads "AC OFF" and pressing the AC button does nothing. Always says AC OFF and I don't hear the compressor even attempt to kick on or the clutch try to engage.

I replaced one of the air mix actuators - the one all the way to the rear right that's nearly impossible to get at. I can hit the RECIRC button and see the dome-shaped cover over the blower motor move in to place and back to fully open. That actuator appears to be functioning normally (which doesn't = the computer knows that).

Then replaced the the other actuator which is under the glovebox and on the left side - very easy to get at. No change, and still getting the code, service AC system message, AC off on HAVC panel, & no compressor running.

Running thru the code detection/clearing sequence with the engine running and clearing [attempting to at least] will still not clear the code or allow the compressor to kick on. I did it the right way w/ engine off several times as well prior to w/ engine running.

I do not have A/C hi/low gauges but do have the much-despised can of R134a w/ gauge. Gave it a quick shot from the can. Not much, just a little to boost the pressure some in case it was a low refrigerant issue preventing compressor from engaging.

Was also getting code B1343 which is Air Inlet Door Movement Fault. That code cleared with the on-board display process and hasn't returned. The Soleus scan tool would not clear it. Possibly changing the actuators fixed that piece, the scan tool wasn't capable but the on-board was, or I haven't left it running long enough to register that code again.

Anyway, I'm not really sure where to go from here. The actuators weren't crazy expensive at around $60 ea, but i don't want to continue randomly replacing parts that *might* be the problem.

I just got the car, so I don't have good behavior from the AC system to use as a reference. I am thinking it's something computer-related only because I've read a lot of similar posts of people whose compressors were still kicking on even though they had misbehaving actuators. It didn't seem like just a faulty actuator alone disabled the compressor and the AC button on the HVAC control panel. Seems like most with similar codes had blend or temperature control problems, but the overall system was still operating. Could be way off - I'm no mechanic.

[rockfangd]

This may sound weird but I highly sugggest unhooking the battery for about 5 minutes.

Then hook it up.

Turn the key on engine off.

dont do anything else for 1 minute. This should give the actuators time to cycle.

See if code is still present.

Let us know what the result is.

Welcome to Caddyinfo forum.

I completely agree on not wasting good parts

[CMV]

Will give it a shot. I did leave the battery disconnected for about 15 min in hopes that would clear the codes but no luck.

hook the battery back up and then just put the key in ignition? Leave in the off position?

What is strange is both actuators (if threre is a third, it's well hidden) seem to function properly. Temp goes up and down on both sides, recirc works, etc. I'm wondering if it isn't a PCM issue - the actuators are doing their thing but the PCM doesn't get the feedback that they repositioned. But I'm just guessing since it really has me stumped.

Jumping the a/c clutch relay the compressor will run and I'm not losing refrigerant. So hopefully I can get it figured out.

[KHE]

The ACM controls the HVAC system, not the PCM. I doubt the ACM is the issue. It is strange that the compressor won't engage yet there is not a low refrigerant code stored. Can you run the codes using the onboard diagnostics and post the results? With the ignition in the ON position, press and hold the OFF and INFO UP buttons on the dash. After a segment check, ALL? will be displayed. ON/OFF="Yes" and INFO RESET = "No". The INFO button is the manual toggle.

[CMV]

Even more stumped than before. I think I'm going to call it quits & take it to a shop.

My observation from earlier was incorrect. The drivers side temp controls work normally. The passenger side will go from clod to hot but then stays stuck on hot & not come back down. Either the replacement actuator is faulty or there is a physical obstruction.

Now in addition to B1341 Air Mix Door Two Movement Fault code I have these gems:

B1324 A/C Refrigerant Overpressure

P0533 Air Conditioning (A/C) Refrigerant Pressure Sensor Circuit High Voltage

Makes sense right? Peter around with 'magic AC repair in a can" and that's bound to happen.

But here's the real kicker - High & Low pressures are reading 0's. I might not be using the gauge & manifold set correctly, but verifying with the magic can & low is at 0 psi. Engine running, HVAC controls set to max AC (AC OFF) indicated as pressing the AC button does nothing, clutch relay jumped, visually see the compressor spinning.

All valves on manifold and connectors fully open. Just to make sure - some need to co clockwise, some counterclockwise - I tried multiple combinations and also reseating the connections on the ports several times. But I did verify with the magic can gauge and it too reads hardly any low side pressure.

Didn't want to risk tearing up [what may be] a perfectly good compressor so I left it running jumped no more than 30-45 sec at a time & no more than 2 min total.

SO my sensors are tellimg me I'm overpresuure, but the gages are telling me I have no pressure.

Just to verify I can figure out how to hook up & read a gauge, I put them on my F150.

[rockfangd]

you may be low on charge but a code will set.

As for resetting the battery you turn the key to the on position but do not start it. then let it sit for 1 minute without touching anything.

If the door is getting stuck at hot it likely needs to be reset because it is not timed properly

[KHE]

Sometimes the gages won't depress the schrader valves on the car fittings. You should be able to measure the vehicle fitting and the hose fitting to see if the gage hoses are able to depress the va;ves on the car side of the system.

[CMV]

Why would it set an overpressure code? Shouldn't it be the opposite? Blocked port and sensor sees high pressure? should still get a read of more than a few psi at the low side if that were the case?

Would manually moving the actuator get it back synchronized or is that something that must be done with a scan tool?

[KHE]

If there is an over-pressure code, the system is overcharged. The gage set is not depressing the valves on the car.

[CMV]

Sometimes the gages won't depress the schrader valves on the car fittings. You should be able to measure the vehicle fitting and the hose fitting to see if the gage hoses are able to depress the va;ves on the car side of the system.

That could be. Probably a bad idea to depress one with a punch and see if anything comes out. But that's all I can think to do. I borrowed the gauge/manifold from AutoZone so I can't modify it.

I think Im beyond my skill set with this. Should probably leave it to someone who knows what he's doing. I'll tinker some more with the air movement door fault. That will be one less thing to have to pay a shop to fix at least if I can correct that.

[CMV]

Still getting code B1324 while pulling a vacuum. I'm going to go out on a limb & say the refrigerant pressure sensor is faulty.

My B1341 has cleared. I put another actuator in place. This time before I did anything I set the pass side temp at 75° which should be center. Then I pulled the actuator, moved the door to middle position, and placed the new actuator. I watched it cycle several times. It moves very slowly - takes about 45 sec to go from one extreme to the other. The driver's side seems to move much faster, but I didn't remove panels to watch it - just gauged by how quickly the air seemed to go from hot to cold (well not 'cold' since it's blowing 105° on cold).

I have a suspicion that code will return as soon as I start up & move pass temp control. The door seems to move freely by hand, With no actuator I can turn the 'nub' and move the door by hand, but it feels like there's drag on it. Maybe it is supposed to move slowly with the actuator, but it's at least 30 - 45 sec to go from full hot to full cold positions. Seems like it should go much faster. But for all I know the pass side responds slower than the driver's?

Letting it stay at vacuum overnight to see if there are leaks or if it holds. Will replace sensor & see if code goes away. Then it goes to the shop to get filled or fixed.

I'm very tempted to try to fill it from the cans just to see if I get cold A/C, but will resist the urge & let a shop do it. No idea if those cans are the right proportions of oil to refrigerant or if there's a good chance of destroying other components doing that. YouTube makes it look so easy......

[KHE]

You can use cans of R-134a to fill the system - it's more cumbersome vs. using a 30 lb. cylinder on a digital scale. I think your car takes 2 lbs. of R-134a (there should be a label on the accumulator). If so, it will take 3, 12 oz cans. Don't worry about the extra 4 oz as you will lose some refrigerant when burping the air from the charging hose.

[CMV]

Changing the refrigerant pressure sensor was the key. Surprisingly easy to get to and swap out - I was expecting a component mounted on the compressor to be a bear to get at. But that made the overpressure code go away and allowed the compressor to kick on like it should and restored functionality of the AC button on the HVAC control panel.

I have a leak at the refrigerant temp sensor. That's along the low pressure line about 24" behind the port, where it makes a 90° bend and the line is along the firewall.

What's strange is it held vacuum, but it did leak enough while charging I could see a little green ooze out and a drop pool where the rubber coating is cut out. I have a new suction line assembly ordered. In the meantime, I tried some JB weld yesterday. No idea if that will work, but won't hurt anything if I'm swapping that whole line assembly out anyway. I left that to cure and will put a little more on after work tonight - that stuff likes to run.

When the new part gets here sometime this week, I don't know if I should attempt to swap it myself. It looks pretty straightforward, but I'm not sure how complicated it will be in reality. The alldata diy steps say to remove the front air deflector but don't really detail how to do that or if anything else has to be removed to make that happen. Just need to look at it I guess.

It looks like someone put a wrench at the sensor and tried to remove it. That part of the line that looks like a nut. Not sure why since that sensor just pops out, but it looks like the line is twisted a little right at that 'nut'. Apparently there's someone out there worse at working on A/C systems than me