AC Problem ?

[J33Pfan]

02 4WD V6 Unlimited

Last Summer my daughter complained that the AC went warm after driving around a bit.

The other day I hooked up gauges to my AC system to see if it needed anything as I am planning to evacuate & charge the system. The AC was very cold the whole time. It was about 60 degrees outside.

I turned the AC on and observed the following:

*The Low side read 50 Psi while the compressor was cycled Off. Then 25 Psi with the compressor engaged.
*The High side read 200 Psi with the compressor Off. Then 150 Psi with the compressor engaged.
(The Psi moved up and down a bit throughout the testing.)

The (one) electric fan I have cycled on when the compressor cycled ON but it did not always come on at the same time the compressor was engaged.

#Does anybody familiar with this AC system see any problems??

# If I'm going to evacuate & charge the system do I need to change the Orifice tube/hose or accumulator?

#Can you change the Orifice without replacing the hose?

 

[uss2defiant]

# If I'm going to evacuate & charge the system do I need to change the Orifice tube/hose or accumulator?

#Can you change the Orifice without replacing the hose?

1. you do not need to unless if you open the system.
2. No. the orifice is inside the low side line aluminum tubing.

I'm not an A/C tech but according to the table in the FSM, it's within operating specifications.
Here's a link to my post some time ago.
https://www.jeepkj.com/threads/ac-s...nd-refrig-oil-amount-performance-chart.58537/

 

[J33Pfan]

1. you do not need to unless if you open the system.
2. No. the orifice is inside the low side line aluminum tubing.

I'm not an A/C tech but according to the table in the FSM, it's within operating specifications.
Here's a link to my post some time ago.
https://www.jeepkj.com/threads/ac-s...nd-refrig-oil-amount-performance-chart.58537/

thanks
Good link but all your photos are not showing

 

[uss2defiant]

use the PDF version at the bottom.
I did that in case the links to the photos ever broke.

 

[J33Pfan]

1. you do not need to unless if you open the system.
2. No. the orifice is inside the low side line aluminum tubing.

I'm not an A/C tech but according to the table in the FSM, it's within operating specifications.
Here's a link to my post some time ago.
https://www.jeepkj.com/threads/ac-s...nd-refrig-oil-amount-performance-chart.58537/

WARNING!! I saw 3 pages of info, thanks ..but that web page is trying to get me to download a PDF program telling me there is a problem with my PDF reader. and trying to add a lot of Pop up notifications.

 

[uss2defiant]

oh sorry. never noticed it since I have adblocker on my browser.

 

[Birdman330]

The AC button on the HVAC controls is known to short out. Happened to me, it was an easy fix ordering a new control unit. Just diagnosing the problem was a headache because the symptoms act like a low or high side sensor failing.

 

[uss2defiant]

The AC button on the HVAC controls is known to short out. Happened to me, it was an easy fix ordering a new control unit. Just diagnosing the problem was a headache because the symptoms act like a low or high side sensor failing.

There's no A/C button for the early models.

 

[J33Pfan]

Is the Jeep different? Most other cars I serviced keeps the electric fan on almost constantly with the AC on. My Fan goes on part of the time with the AC clutch engaged. Is this normal? ... at 65 deg temps outside.

 

[Billwill]

The Ac cycles ON/OFF at all times even if AC is not turned ON.

I believe that the cooling fan is controlled by a thermal sensor somewhere but my Manual 2002 Export CRD does not have an electric fan at all so I am not sure here. I also do not have a push-button switch. I believe they started fitting fans on the Export models once they went Automatic.

Download the 2002 Jeep KJ Service Manual here...gives you the Theory of Operations and section 8W has the Wiring Diagrams.

Jeep KJ Service Manuals: www.colorado4wheel.com/manuals/Jeep/KJ

 

[uss2defiant]

Do you have access to the FSM?
Most of what you seek will be in there.

To answer your question, yes it is normal.
See thread for the operating conditions.
https://www.jeepkj.com/threads/electric-fan-question.57939/

 

[J33Pfan]

Do you have access to the FSM?
Most of what you seek will be in there.

To answer your question, yes it is normal.
See thread for the operating conditions.
https://www.jeepkj.com/threads/electric-fan-question.57939/

Great links thanks!

I copied it here too

The e-rad fan only comes on at certain conditions.

OPERATION
The electric radiator cooling fan is controlled by the Powertrain Control Module (PCM) through the radiator cooling fan relay. The PCM regulates fan operation based on input from the engine coolant temperature sensor, battery temperature sensor,air
conditioning select switch and vehicle speed. The fan is not energized during engine cranking regardless of the electrical input from the temperature sensors and ,air conditioning switch. However, if engine operation conditions warrant fan engagement, the fan will run once engine starts.

Vehicles Equipped with AC:
In addition to using coolant temperature and battery temperature sensor to control cooling fan operation, the cooling fan will also be engaged when the ,air conditioning system is activated. The relay is also energized when, air conditioning is selected and coolant temperature is above 95° C ( 203° F), or , air conditioning is selected and battery temperature sensor is above 41° C (106°F). It will then de-energize when , air conditioning is selected and coolant temperature is below 92° C (198° F), or , air conditioning is selected and battery temperature is below 38° C (100° F).