2010 Nissan Sentra ac clutch won't engage. Replaced fuse box relay control module, replaced all switches inside the car that control fan and ac, checked wiring from ac compressor clutch to fuse/relay

How do you know it's not too high or low on refrigerant if it won't run? And yes, bypassing the pressure switch should engage the compressor as well as the fans. I think it is low on 134a and if you can add some, the compressor will start up. Also, notice that in extremely cold weather the A/C will not come on because low pressure condition is detected by the low pressure switch. Make sure your A/C settings are low enough to turn the system on. Winter here is not that hot.

We had it charged at a shop prior. So it is charged. Bypassing the pressure switch only seems to turn the fans on not the compressor. The fuse is good and has power. The wiring is good from the module to the compressor and I can power it up at the module where the wire from the compressor comes to the box module. Seems the module is not providing the signal for it to turn on. I have replaced the module and still have the same issue. I also replaced the controls inside the car. What am I missing here. Or do I possible have a bad module still even though it was replaced? Thanks for your responses

I found one pressure switch I hear there are two A high and low. All I see I'd the one on the front drivers side behind the grill. Where is the other on located. Thank you

The switch you found toward the grill near the condenser is the high pressure switch that cuts out if over charged, overly hot day, fans stopped, condenser clogged. The other is the low pressure switch mounted on the line nearer the evaporator on the suction (cold) line near the accumulator. They both should be closing the circuit electrically, to make things run. Ohm meter showing continuity across the switch terminals. I would talk to the shop that recently serviced your vehicle.

There's is no Low Pressure Switch that I can find. I have pulled the entire dash apart inside all the way to the condenser, I have traced all pressure lines cold and return from end to end and visibly looked for another switch. All I have is the single pressure switch behind the grill on top on the drivers side. Only one other connection is at the compressor pump. Please help

I'm thinking it is the pressure switch. It's a 3-wire switch and I'm trying to figure out how to test it. If it is I will have to drain and refill the system which sucks but I want to be sure as possible before I go through all that.

Still waiting for some help here to my previous post. Not the fuse/relay control box, not a fuse, not the gauges or switches inside the car, not the compressor, need to know how to check the pressure switch. There is only one on the front driver side just behind the grill. Any help would be appreciated. Next step is to replace the switch but the system will need to be vacuumed out and refilled so I want to be sure prior to taking this next step. Thanks in advance for your responses

Number 16 is low pressure ac switch. I've been working on this problem too. I'm hopeful this will fix my problem, compressor clutch not engaging. I'm pretty sure I ran outta 134 as it was steadily not as cold. We'll see how this goes but I'm sure knowing this part will help someone.