Ac charging

Turtle

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In the past, I've just normally added r134a to my cars and no issues every like 3 years. Get them in the nice 40-45 psi and it's cold. Yea it might be a hack way but $10 for a can every 3 years is golden to me.

So now I tired to help some friends on their Honda products. Same process but the r134a wouldn't go into the system. Ac button is on. Fans were on. Couldn't see the compressor or hear it kick on. But psi was in the 100-110.

Had the car warmed up. Rev to 3k. 15 minutes later the 12oz can was still full. I disconnected to see if I pierced the can. And sure enough I did. Why won't the system take it?

Should I try to jump the relay? Or is there a switch on these Honda.
 

cap42

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Forget the name of it but there is a high/low pressure switch you jump with a paper clip to get the compressor running. Then it will draw in the refrigerant.
 

OffshoreDrilling

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that is plenty of pressure that the compressor should be running, if you're measuring it on the low side of the system. At 80* r134's saturation pressure is just over 85lbs so of course it's not going to suck anything in. Your issue isn't being low in refrigerant at this point. the low pressure switch should open the circuit at somewhere about 25lbs
 

bikrboy128

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what year and make honda?
"newer" hondas are known for their compressor relays going bad. find it in the fuse box, figure out the pinout, and jump it to see if it works

also, there's a thermal protector switch on the compressor itself that's known to fail. the one wire going to the compressor is actually going to the switch. it should have 12 volts. jump the 12v input wire to the wire going to the clutch to see if the compressor kicks on. the switch is serviceable without emptying the system, you just need to dig it out.
 
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Turtle

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that is plenty of pressure that the compressor should be running, if you're measuring it on the low side of the system. At 80* r134's saturation pressure is just over 85lbs so of course it's not going to suck anything in. Your issue isn't being low in refrigerant at this point. the low pressure switch should open the circuit at somewhere about 25lbs
Yea my little cheap r134a tool only does low side.
what year and make honda?
"newer" hondas are known for their compressor relays going bad. find it in the fuse box, figure out the pinout, and jump it to see if it works

also, there's a thermal protector switch on the compressor itself that's known to fail. the one wire going to the compressor is actually going to the switch. it should have 12 volts. jump the 12v input wire to the wire going to the clutch to see if the compressor kicks on. the switch is serviceable without emptying the system, you just need to dig it out.
Early 2000 Base civic sedan with the 1.7.

And a rdx. The one with turbo engine.

Both cars had 150k miles on it. The civic a/c just stopped working. Was working ealier the season. I can physically see the fans kick on. Rpm go up. But couldn't see and hear the click from compressor.

The rdx... well that one didn't have ac for like 2 years. And it was a spur of the moment, middle of the night attempt to recharge. I didn't look at fans or compressor. Just turned on the a/c and tired to charge.

Both read somewhere in low 100s on the low side. I was going to look for the relay and fuses but I guess Honda does label it AC compressor. I saw 2 snowflakes on a the rdx box.
 

bikrboy128

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Yea my little cheap r134a tool only does low side.

Early 2000 Base civic sedan with the 1.7.

And a rdx. The one with turbo engine.

Both cars had 150k miles on it. The civic a/c just stopped working. Was working ealier the season. I can physically see the fans kick on. Rpm go up. But couldn't see and hear the click from compressor.

The rdx... well that one didn't have ac for like 2 years. And it was a spur of the moment, middle of the night attempt to recharge. I didn't look at fans or compressor. Just turned on the a/c and tired to charge.

Both read somewhere in low 100s on the low side. I was going to look for the relay and fuses but I guess Honda does label it AC compressor. I saw 2 snowflakes on a the rdx box.
for the civic: check the thermal cutoff switch. unfortunately on the 1.7s it's a bitch to get to. you should see the connector on the side of the radiator fan. one wire leading down to the compressor. check for voltage with the engine on and ac switched on.
if you have 12+ volts on that wire, you know to dig deeper. if jumping the thermal switch still doesn't kick the compressor on, you have a bad clutch.

the RDX: since nothing is happening (the fans or compressor aren't kicking on) i'd guess the relay first. every honda from.....probably 06+ uses a solid state relay that will fail without warning. on the fusebox there should be a picture of a snowflake, a snowflake and fan, and just a fan. the clutch relay is the snowflake only, which should be a black relay. try either switching it with another relay in the box or just jumping it.


let me know what you find! :bigthumb:

fyi. that can of garbage you buy at the parts store probably has a sealant in it, which is going to clog and destroy your ac system. i wouldn't suggest using it
 
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Turtle

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for the civic: check the thermal cutoff switch. unfortunately on the 1.7s it's a bitch to get to. you should see the connector on the side of the radiator fan. one wire leading down to the compressor. check for voltage with the engine on and ac switched on.
if you have 12+ volts on that wire, you know to dig deeper. if jumping the thermal switch still doesn't kick the compressor on, you have a bad clutch.

the RDX: since nothing is happening (the fans or compressor aren't kicking on) i'd guess the relay first. every honda from.....probably 06+ uses a solid state relay that will fail without warning. on the fusebox there should be a picture of a snowflake, a snowflake and fan, and just a fan. the clutch relay is the snowflake only, which should be a black relay. try either switching it with another relay in the box or just jumping it.


let me know what you find! :bigthumb:

fyi. that can of garbage you buy at the parts store probably has a sealant in it, which is going to clog and destroy your ac system. i wouldn't suggest using it
Will report back. I should see the rdx tonight, if he is driving it. Civic I might not see for a while as it's just a daily work car for my friend, plus he doesn't care too much about it.


I don't buy the cans with sealers. Just straight r134a 12oz cans.
 
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Turtle

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So guy stopped by with the rdx. He went to get the ac charged by a shop and well. It didn't work.

It held vacuum but didn't take the charge. Not sure if that's possible. But it's still not working and the system is completely empty.

I told him about the relay. And now it makes even more sense. He said he was going to get a relay and comeback later.

Everything is pointing to a bad relay.
 

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