Ground the other probe from the meter by touching it to any nearby bare-metal surface on the system. How do you test a 3 wire AC Pressure Switch.
If not jump the yellow with the yellow and black this should turn the compressor on here is the ac wiring diagrams below so you can see how the system works.
How to test 3 wire ac pressure switch. HOW TO TEST AC PRESSURE SWITCH ON CHEVY CHEVROLET GMC BUICK CADILLAC AC NOT WORKING Great Car Scanner. Check the pressure of the air conditioning system by attaching a low pressure gauge from a refrigerant recharge kit to the low pressure fitting located between the accumulator and the compressor and marked with a capital L According to AA1 Car on an 80 degree day the low pressure gauge should measure 56 psi pounds per square inch or higher. On most sensors when you look at the base of the sensor connector you can find description for the wires.
Check the numbers printed on your AC and connect wires according to it. So ive sent him back to the place that regassed the AC to have it pressure checked. The three wire switches is also called as pressure transducers.
I would check for a leak as well. Air conditioning pressure sensors also known as AC switches turn off a cars air conditioning system whenever the refrigerant pressure reaches a lower extreme. This is done to power the compressor clutch.
Step 3 Touch one of the probes from the meter to either one of the terminals on the pressure switch. Ive tested the voltage on the signal wire at the ECU and got 02v with engine running and AC on. Connect the wires according to the numbers printed on it.
If the AC pressure switch is bypassed then the compressor can potentially freeze up from a lack of fluid and lubrication requiring expensive work to be done by a professional mechanic. These are used with GM variable control compressors and displacement compressors. Maybe they filled it and didnt check for leaks.
Continuity Reference Voltage Source Voltage Signal Voltage Voltage Drop and Resistance. According to expert maintenance tips it is essential to follow the previous readings in mind. It does the process by monitoring fan operation high pressure and low pressure then sending the information back to the computer for it to analyze.
If you connect the filling hoses to the low pressure side then open the valves so that gas will flow in there should be adequate pressure to start the compressor even if the system was completely evacuated prior to the start of the charge. When the electrical connection is working as it should the multimeter will read between 40 and 50 volts. Just open the gauge and let the system take in refrigerant and the system will kick on.
I have two white wires with black stripes and a green wire with a black stripe and a yellow wire with a black stripe I checked all the wires going into the switch and I have power on all of them not sure if they are the correct amounts though You are talking about the high and low pressure combination switch for the AC system on the high side correct. Put the multimeter in the Ohms position usually displayed with the Ω symbol. Unplug the single wire connector on the front side of the compressor.
How To Jump 3 Wire AC Pressure Switch. You have to bypass 3 wire ac pressure switch from B1 to B4 to power up the compressor clutch. Make sure your key is turned on to the accessories spot.
You need to bypass 3 wire AC pressure switch through the B1 to B4. Attach the other end of the jumper wire to the positive terminal of the battery. I think the problem lies in the low voltage coming out the sensor.
When you do this the connection will send 0-5 volts of pressure through the PCM fuse. When the pressure increases from charging the compressor will kick on. Take the pressure sensor off and test the connection heading to the sensor from the electrical harness.
The connection sends 0-5 volts of pressure to the PCM fuse. Set the voltmeter or multimeter to display AC volts. Also since there is no accumulator in between the compressor and the low side port.
Take the fused jumper wire and connect its one end to that side of the wire connector that was connected to the compressor. AC Pressure Switch Replacement Cost. At the core a pressure switch is the same as any other switch.
This means that once the component a pressure switch in this case is disconnected from the main body the AC unit in this case you can test the pressure switch as you would any switch. Jul 23 2006. Unlike the other systems in a car the air conditioning system has a sensitive part that could cost you a lot in the long run once they start to failAlthough this system is one of the splendid resources that car owners everywhere enjoy it may be quite problematic if it is left unchecked.
Here is the procedure to test any 3 wire pressure sensor First find out pinout for sensor.