Sorry for the long post.

I live in central FL and I have black '99 EB Expy. I bought the truck in 2005 with about 75k miles on it. Since I have owned it, I was never happy with the performance of the A/C, especially if I left it on Automatic Temperature Control (Max would usually do the trick). Back then, I had my mechanic look at it and he could not make it perform any better. He replaced the compressor, but that did not seem to make much of a difference.

Now the problem seems worse. I have a leak in the system, because I put a can of freon with stop-leak in the spring and I just had to add another can. After adding the freon I can feel colder air coming out of the vents and it gets really cold in the early morning or at night, but when it is really hot outside it takes a while for the air coming out of the vents to get cold.

What I have noticed on a hot day is that it starts to finally blow the coolest after I have driven around for about 5 minutes. If I am sitting in a parking lot for an extended period of time right after start-up the air coming out of the vents is cool, not cold. Also on hot days, even after driving around for a while, if I stop for an extended period (waiting for the wife in a store) the air start blowing cool (not cold) again.

Of course I realize that the car will cool down faster if I roll the windows down and drive around right after start up, but I am talking about the temperature of the air coming out of the vents, not the temperature of the car's interior.

So does this sound like a blend door problem (maybe not closing completely), or do I just need to add more freon? Has anyone had any luck with evacuating the system and recharging with new freon?

 

You might have to bite the bullet and go to a shop that specializes in A/C for a diagnosis and service. My Navigator was not cooling this spring and I just added R134, using the gages, and ever since then the A/C will freeze me out when on max cool! This is even when we have had some 100* or more days. On normal cool it is not nearly as cold at the vents. On max cool the air at the middle vents is at 26* or so. I've never had such good, cold A/C with R134 before.

 

Yeah, I thought about that. Free AC check right?

I have a feeling that it will never work out to be free, but maybe they can tell me something. Thanks for the advice.

 

If the A/C charge presure is not correct, it will not operate properly. I also had a problem like yours on my 00 F350. I know, not the same truck LOL. It was the cycleing switch the first time (your MOTORCRAFT # yh-562). A couple years later, same symtoms, but it was the pressure cut off switch (your Ford # F5TZ-19D594-AA) Just a couple of thing you could look at easily. Good luck.

 

I never said "Free"
You're in Florida and you know that it is only to get you in there so they can get the job. They will however, give you a sincere and free handshake. I really think that you will be treated well by amost any reputable A/C shop.

 

Thanks!

By check, do you mean replace and see if it fixes the issue, or is there a way to test these two switches? I check alldata and did not see a diagnostic procedure...

 

Let me see if I can find the info.

 

<TABLE border=1 rules=groups cellSpacing=0 cellPadding=3 width="90%"><TBODY><TR vAlign=top><TD>

• The A/C does not operate/does not operate correctly — EATC

</TD><TD>

• Open fuse.
• Circuitry short/open.
• A/C cycling switch.
• A/C system discharged/low charge.
• A/C pressure cut-off switch.
• A/C control.

</TD><TD>

• GO to Pinpoint Test H.

</TD></TR></TBODY></TABLE>

 

PINPOINT TEST H: THE A/C DOES NOT OPERATE OR DOES NOT OPERATE CORRECTLY—EATC

<TABLE border=1 rules=groups cellSpacing=0 cellPadding=3 width="96%"><COLGROUP><COLGROUP><TBODY><TR><TH>CON DITIONS</TH><TH>DETAILS/RESULTS/ACTIONS</TH></TR></TBODY><TBODY><TR><TD colSpan=2> H1 CHECK THE PID WACF WITH THE A/C OFF</TD></TR></TBODY><TBODY><TR><TD colSpan=2>NOTE: When PCM PID WACF is YES, this is the same fault as DTC P1460.</TD></TR><TR><TD colSpan=2>NOTE: The outside air temperature must be over 10° C (50° F).</TD></TR><TBODY></TBODY><TBODY><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top></TD><TD vAlign=top>Press the OFF button on the electronic automatic temperature control module.
</TD></TR><TR vAlign=top><TD vAlign=top>
PCM PID WACF</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD></TD><TD>

• Does the PCM PID WACF read YES?

Yes REFER to the Powertrain Control/Emissions Diagnosis (PC/ED) manual to continue the diagnosis.

No GO to H2.
</TD></TR><TBODY><TR><TD colSpan=2> H2 CHECK PID WACF WITH THE A/C ON</TD></TR></TBODY><TBODY><TR><TD colSpan=2>NOTE: When PCM PID WACF is YES, this is the same fault as DTC P1460.</TD></TR><TBODY></TBODY><TBODY><TR vAlign=top><TD vAlign=top></TD><TD vAlign=top>Start the engine and run at idle.
</TD></TR><TR vAlign=top><TD vAlign=top></TD><TD vAlign=top>Press the EATC MAX A/C override button.
</TD></TR><TR vAlign=top><TD vAlign=top>
PCM PID WACF</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD></TD><TD>

• Does the PCM PID WACF read YES?

Yes REFER to the Powertrain Control/Emissions Diagnosis (PC/ED) manual to continue the diagnosis.

No GO to H3.
</TD></TR><TBODY><TR><TD colSpan=2> H3 CHECK PID ACCS WITH THE A/C ON</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top></TD><TD vAlign=top>Make sure the engine is at idle.
</TD></TR><TR vAlign=top><TD vAlign=top></TD><TD vAlign=top>Press the EATC MAX A/C override button.
</TD></TR><TR vAlign=top><TD vAlign=top>
PCM PID ACCS</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD></TD><TD>

• Does the PCM PID ACCS read ON?

Yes GO to H4.

No GO to H5.
</TD></TR><TBODY><TR><TD colSpan=2> H4 CHECK PID WAC WITH THE A/C ON</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top></TD><TD vAlign=top>Press the EATC MAX A/C override button.
</TD></TR><TR vAlign=top><TD vAlign=top>
PCM PID WAC</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD></TD><TD>

• Does the PID WAC read ON?

Yes GO to H15.

No REFER to the Powertrain Control/Emissions Diagnosis (PC/ED) manual to continue the diagnosis.
</TD></TR><TBODY><TR><TD colSpan=2> H5 CHECK POWER INPUT TO THE PCM</TD></TR></TBODY><TBODY><TR><TD colSpan=2>NOTE: Do not directly probe the PCM wire harness connector.</TD></TR><TBODY></TBODY><TBODY><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>
Powertrain Control Module C174</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top></TD><TD vAlign=top>Connect the EEC-V 104 Pin Breakout Box to the wire harness connector C174. Do not connect the breakout box to the PCM.
</TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top></TD><TD vAlign=top>Press the EATC MAX A/C override button.
</TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>Measure the voltage at breakout box Pin 41, Circuit 347 (BK/Y).
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the voltage greater than 10 volts?

Yes INSTALL a new powertrain control module; refer to Section 303-14. TEST the system for normal operation.

No GO to H6.
</TD></TR><TBODY><TR><TD colSpan=2> H6 CHECK THE REFRIGERANT SYSTEM PRESSURE</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top></TD><TD vAlign=top>Connect the manifold gauge set to the service ports; refer to Manifold Gauge Set Connection in this section.
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the pressure reading between 345 kPa (50 psi) and 1724 kPa (250 psi)?

Yes GO to H7.

No CHECK the system for refrigerant system leaks; refer to Leak Detection—Using Auto Calibration and Leak Detection—Using Auto Calibration in this section.
</TD></TR><TBODY><TR><TD colSpan=2> H7 CHECK CIRCUIT 348 (P) FOR AN OPEN</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top>
EATC connector C281</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>
Refrigerant Containment Switch C170</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>Measure the resistance of Circuit 348 (P) from the refrigerant containment switch connector C170 to the EATC connector pin C281-11.
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the resistance reading less than 5 ohms?

Yes GO to H8.

No REPAIR Circuit 348 (P) for an open. TEST the system for normal operation.
</TD></TR><TBODY><TR><TD colSpan=2> H8 CHECK CIRCUIT 348 (P) FOR A SHORT TO GROUND</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>Measure the resistance between the refrigerant containment switch connector C170, Circuit 348 (P) and ground.
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the resistance reading greater than 10,000 ohms?

Yes GO to H9.

No REPAIR Circuit 348 (P) for a short to ground. TEST the system for normal operation.
</TD></TR><TBODY><TR><TD colSpan=2> H9 CHECK VOLTAGE AT REFRIGERANT CONTAINMENT SWITCH</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top>
EATC connector C281</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top></TD><TD vAlign=top>Push the EATC MAX A/C override button:
</TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>Measure the Voltage of Circuit 348 (P) at the refrigerant containment switch connector C170.
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the voltage reading greater than 10 volts for each position?

Yes GO to H10.

No INSTALL a new EATC module. TEST the system for normal operation.
</TD></TR><TBODY><TR><TD colSpan=2> H10 CHECK CIRCUIT 441 (R/Y) FOR A SHORT</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top>
A/C Cycling Switch C139</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>Measure the resistance between A/C cycling switch connector C139, Circuit 441 (R/Y) and ground.
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the resistance reading greater than 10,000 ohms?

Yes GO to H11.

No REPAIR Circuit 441 (R/Y) for a short. TEST the system for normal operation.
</TD></TR><TBODY><TR><TD colSpan=2> H11 CHECK CIRCUIT 441 (R/Y) FOR AN OPEN</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>Measure the resistance of Circuit 441 (R/Y) from the A/C cycling switch connector C139, to the refrigerant containment switch connector C170.
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the resistance reading less than 5 ohms?

Yes GO to H12.

No REPAIR Circuit 441 (R/Y) for an open. TEST the system for normal operation
</TD></TR></TBODY></TABLE>

 

<TABLE border=1 rules=groups cellSpacing=0 cellPadding=3 width="96%"><TBODY><TR><TD colSpan=2>H12 CHECK THE A/C CYCLING PRESSURE SWITCH</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>
A/C Cycling Switch C155</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>Measure the voltage of Circuit 441 (R/Y) at A/C cycling switch connector C139.
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the voltage reading greater than 10 volts?

Yes GO to H13.

No INSTALL a new refrigerant containment switch. TEST the system for normal operation.
</TD></TR><TBODY><TR><TD colSpan=2> H13 CHECK CIRCUIT 347 (BK/Y) FOR A SHORT</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>Measure the resistance of Circuit 347 (BK/Y) between the A/C cycling pressure switch and ground.
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the resistance reading greater than 10,000 ohms?

Yes GO to H14.

No REPAIR Circuit 347 (BK/Y) for a short to ground. TEST the system for normal operation.
</TD></TR><TBODY><TR><TD colSpan=2> H14 CHECK CIRCUIT 347 (BK/Y) FOR AN OPEN.</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>Measure the resistance of Circuit 347 (BK/Y) between the A/C cycling pressure switch and PCM breakout box pin 41.
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the resistance reading less than 5 ohms?

Yes INSTALL a new A/C cycling switch. TEST the system for normal operation.

No REPAIR Circuit 347 (BK/Y) for an open. TEST the system for normal operation.
</TD></TR><TBODY><TR><TD colSpan=2> H15 CHECK CIRCUIT 295 (LB/PK) FOR A SHORT</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top></TD><TD vAlign=top>Remove Fuse 5 (15A).
</TD></TR><TR vAlign=top><TD vAlign=top>
A/C Clutch Relay</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>Measure the resistance to ground at A/C relay pin 3, Circuit 295 (LB/PK).
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the resistance reading less than 10,000 ohms?

Yes REPAIR Circuit 295 (LB/PK) for a short to ground. TEST the system for normal operation.

No GO to H16.
</TD></TR><TBODY><TR><TD colSpan=2> H16 CHECK CIRCUIT 295 (LB/PK) FOR AN OPEN</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top></TD><TD vAlign=top>Install a new Fuse 5 (15A).
</TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>Measure the voltage between the A/C clutch relay connector Pin 3, Circuit 295 (P/O) and ground.
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the voltage reading greater than 10 volts?

Yes GO to H17.

No REPAIR Circuit 295 (LB/PK) for an open. TEST the system for normal operation.
</TD></TR><TBODY><TR><TD colSpan=2> H17 CHECK THE A/C CLUTCH RELAY</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>
A/C Clutch Relay</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>
A/C Clutch Coil Connector C106</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD></TD><TD>

• Does Fuse 5 (15A) open?

Yes GO to H18.

No GO to H20.
</TD></TR><TBODY><TR><TD colSpan=2> H18 CHECK CIRCUIT 321 (GY/W) FOR A SHORT</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>
A/C Clutch Relay</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>Measure the resistance to ground of Circuit 321 (GY/W) at A/C relay pin 5.
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the resistance greater than 10,000 ohms?

Yes GO to H19.

No INSTALL a new A/C clutch relay.
</TD></TR><TBODY><TR><TD colSpan=2> H19 CHECK THE A/C CLUTCH DIODE</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top>
A/C Clutch Diode</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>Measure the resistance to ground of Circuit 321 (GY/W) at A/C relay pin 5.
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the resistance reading less than 10,000 ohms?

Yes REPAIR Circuit 321 (GY/W) for a short. TEST the system for normal operation.

No INSTALL a new A/C clutch diode.
</TD></TR><TBODY><TR><TD colSpan=2> H20 CHECK THE A/C CLUTCH INPUT</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>
A/C Clutch Relay</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>
A/C Clutch Field Coil C106</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>In Active Command Mode, command the PCM outputs ON.
</TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>Measure the voltage at the A/C clutch field coil connector C106, Circuit 321 (GY/W).
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the voltage reading greater than 10 volts?

Yes GO to H22.

No GO to H21.
</TD></TR><TBODY><TR><TD colSpan=2> H21 CHECK CIRCUIT 321 (GY/W) FOR AN OPEN</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>
A/C Clutch Relay</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>Measure the resistance between the A/C clutch relay connector pin 5, Circuit 321 (GY/W) and the A/C clutch field coil connector C106.
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the resistance reading less than 5 ohms?

Yes INSTALL a new A/C clutch relay. TEST the system for normal operation.

No REPAIR Circuit 321 (GY/W) for an open. TEST the system for normal operation.
</TD></TR><TBODY><TR><TD colSpan=2> H22 CHECK THE A/C CLUTCH GROUND CIRCUIT FOR AN OPEN</TD></TR></TBODY><TBODY><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top></TD></TR><TR vAlign=top><TD vAlign=top>

</TD><TD vAlign=top>Measure the resistance between the A/C clutch connector C106, Circuit 57 (BK) and ground.
</TD></TR><TR vAlign=top><TD></TD><TD>

• Is the resistance reading 1 ohm or less?

Yes INSTALL a new A/C clutch field coil . TEST the system for normal operation.

No REPAIR Circuit 57 (BK) for an open. TEST the system for normal operation
</TD></TR></TBODY></TABLE>

 

Well thats them. Have at it.

 

Yowsa! Shouldn't your post have been preceded with "You asked for it!"

So I guess H10-H14 covers the two components you mentioned right?

Thanks by the way.

 

Thems the ones. I figured I'd throw the book at ya LOL. But more info is always better. Right?

 

Just more confusing, for me at least.

 

I feel the same way, but this gives him options. Maybe he feels froggy and wants to test more. IDK.