Bypassing Low pressure switch on 04 Explorer XLT

How do I bypass the low pressure switch so the clutch can engage so I can fill it with R134a+?

Thank you!
EDIT:

You guys are not getting it.

I KNOW HOW to recharge the system with R134. The problem is I CANNOT RECHARGE it because of the low pressure switch that prevents the clutch from engaging. Making it impossible for me to recharge the system.

unplug the electrical connector and jump it with a paper clip.

Okay, which relay do I unplug, and what socket do I put the paperclip endings in? :exp:

you need to find the low pressure cut-out switch. It is inthe low side refridgerant lines of the ac system. not 100% sure where it is on these as I have never needed to know....yet.

I wish there was a diagram on how to do this.

Low press should be a smaller dia line. Another way I give initial charge is disconnect and power the A/C clutch itself so it pumps in the refrigerant.

rocco123 said:

Low press should be a smaller dia line. Another way I give initial charge is disconnect and power the A/C clutch itself so it pumps in the refrigerant.

Click to expand...

Can I have step by step directions on how to do this?

Edit: I know how to charge the system via low pressure port. The problem is the clutch wont engage because of the low pressure switch. Which makes it impossible to recharge the system.

If you are recharging from the small cans you can buy at your local auto parts store, just hold the first can upside down and it will flow into the system. Then finish the charge slower by holding the next can upright.

You guys are not getting it.

I KNOW HOW to recharge the system with R134. The problem is I CANNOT RECHARGE it because of the low pressure switch that prevents the clutch from engaging. Making it impossible for me to recharge the system.

I've never looked on that new of an X, but normally I find them near the accumulator on 1st gens, and on my friends f-150.

I don't know if it will help, but if you flip the can upside down you do get more pressure on the low side. I never "leave it" upside down, but I normally put the first can in alternating from up side down to right side up to keep the pressure about 40 psi.

~Mark

Like Maniak and I have said just turn the A/C on max hook up your hose to the low pressure side with a can of R134a held upside down and soon the compressor will kick on, then fill it slower the rest of the way and you're done.

When I turn the A/C on it will not engage the clutch because there is NO CHARGE in the system. Therefore I CANNOT CHARGE because the CLUTCH IS DISENGAGED. People usually bypasses this low pressure warning by jumping the switch to trick the clutch into engaging even with NO CHARGE.

Now I need to know HOW TO JUMP THIS LOW POWER SWITCH so I CAN CHARGE the system. Thank you

Well, I cant answer the "where question" but I can say we are missing something here..

You do Not need the a/c to engage to start to charge it. You can get 12 ounces or more into a system when it is off. If you put the can in a cup of hot water you can get even more in.


Once you have a can in there the compressor should turn on although it may cycle during the charge process.

~Mark

When the clutch isnt engaged the pressure is in the red zone and the R134a refuses to go into the system. However when the clutch is engaged the pressure is normal, and allows the system to be charged.

Help!

Saik said:

When the clutch isnt engaged the pressure is in the red zone and the R134a refuses to go into the system. However when the clutch is engaged the pressure is normal, and allows the system to be charged.

Help!

Click to expand...

not sure what "the red zone" means. But if the clutch is not engaged there will be no suction on the low side to pull the freon from the can into the system. When the clutch shuts off the pressure in the high side and low side start to equalize, meaning that the pressure on the low side goes up. this is normal.

Saik said:

When the clutch isnt engaged the pressure is in the red zone and the R134a refuses to go into the system. However when the clutch is engaged the pressure is normal, and allows the system to be charged.

Help!

Click to expand...

I looked through rockauto and could not find a picture of where the low pressure switch connects to. I did find a picture of the actual switch and it threads on like I expected it to.

My best guess will be near the accumulator/receiver/dryer..

Also, When you start to charge a system you evacuate it first. This pulls the moisture out of the system and puts a vacuum in the system. This way you can get the first can or so into the system which should be enough to get the compressor to run. It will most likely cycle, but while its cycling it will pull in the r-134 when the compressor is engaged.

Another possible option if you still can't find the low pressure switch to bypass is to power the a/c clutch yourself. Normally its just 12v on 1 side and ground on the other and viola, the clutch is engaged.

One last thing. It sounds like your just using one of those cans with a gauge on it from the auto parts store. Personally I don't like those as they don't normally have pressures listed and you can't know what the high side pressure are either. If your high side pressure gets too high that can also turn of the system on newer vehicles (ones with a high pressure switch too).

~Mark