Another AC compressor/clutch question - ZR-1 Net Registry Forums

mlipmd · 05-21-2022

I recharged my AC system a year ago and now is again low on freon. (Blows warm air, light flashes, code 09).
Last time I had to jump the low pressure switch to get the compressor to turn on so I could start to fill the system, then after a minute or two I could reconnect it and it would cycle on and off as normal as I filled it up.
A few days ago I did that same thing but only had a small 8 oz. can of freon which was not enough to refill the system. The compressor again turned on doing this and when I put the freon it cycled on and off as I recharged it. And it did blow cold air.

Today, with a fresh supply of 12 oz. cans I again tried to recharge it but now the compressor will not turn on, the clutch doesn't engage when I short or bypass the low pressure switch.
The 25 amp AC fuse seems intact, there is no continuity when I measure across the contacts to the connector to the switch ( I don't know if there's supposed to be), so my question is, did the clutch or the compressor blow or is there anything else I can do to try and get the clutch to engage?
The compressor is not locked up, I can turn it freely with the engine off.

I know - One other alternative than just the cans of freon and the included pressure gauge is to get a proper set of gauges and measure both high and low pressures to see what's happening, but it's obvious the system is low.
Another separate question - if you inadvertently fill it up with too much freon, would that cause the clutch to not engage, for the compressor to not turn on?

Thanks for any suggestions.

mlipmd · 05-22-2022

I forgot to disconnect the battery to clear the code before trying to jump the low pressure switch to get the compressor to turn on. You can't add freon unless the compressor is running and maybe the code has to be cleared first. I also just looked it up in the FSM and you must clear the code first.
I'll do that and let you know what happens.

mlipmd · 05-22-2022

Another followup-
All's well now, back in business.
You must clear the 09 code indicating low freon from the computer before you can get the compressor to engage.
You do that by either pulling 2 fuses (ctsy (15a) and AC (25a)) or by disconnecting the battery for at least 30 sec., or better yet, a few minutes.
After clearing the code, the compressor will run by jumping the low pressure switch connector allowing you to put freon in. After a few minutes, when the low pressure builds up enough (30-lbs or so), you can reconnect the plug to the low pressure switch and it will run as intended 'till you fill it all the way up (45lbs.).
So don't forget to clear the code.

05-21-2022	#1
mlipmd Join Date: Mar 2021 Location: Crawfordville, FL Posts: 206	Another AC compressor/clutch question I recharged my AC system a year ago and now is again low on freon. (Blows warm air, light flashes, code 09). Last time I had to jump the low pressure switch to get the compressor to turn on so I could start to fill the system, then after a minute or two I could reconnect it and it would cycle on and off as normal as I filled it up. A few days ago I did that same thing but only had a small 8 oz. can of freon which was not enough to refill the system. The compressor again turned on doing this and when I put the freon it cycled on and off as I recharged it. And it did blow cold air. Today, with a fresh supply of 12 oz. cans I again tried to recharge it but now the compressor will not turn on, the clutch doesn't engage when I short or bypass the low pressure switch. The 25 amp AC fuse seems intact, there is no continuity when I measure across the contacts to the connector to the switch ( I don't know if there's supposed to be), so my question is, did the clutch or the compressor blow or is there anything else I can do to try and get the clutch to engage? The compressor is not locked up, I can turn it freely with the engine off. I know - One other alternative than just the cans of freon and the included pressure gauge is to get a proper set of gauges and measure both high and low pressures to see what's happening, but it's obvious the system is low. Another separate question - if you inadvertently fill it up with too much freon, would that cause the clutch to not engage, for the compressor to not turn on? Thanks for any suggestions. Last edited by mlipmd; 05-21-2022 at 04:59 PM.

05-22-2022	#2
mlipmd Join Date: Mar 2021 Location: Crawfordville, FL Posts: 206	Re: Another AC compressor/clutch question I forgot to disconnect the battery to clear the code before trying to jump the low pressure switch to get the compressor to turn on. You can't add freon unless the compressor is running and maybe the code has to be cleared first. I also just looked it up in the FSM and you must clear the code first. I'll do that and let you know what happens.

05-22-2022	#3
mlipmd Join Date: Mar 2021 Location: Crawfordville, FL Posts: 206	Re: Another AC compressor/clutch question Another followup- All's well now, back in business. You must clear the 09 code indicating low freon from the computer before you can get the compressor to engage. You do that by either pulling 2 fuses (ctsy (15a) and AC (25a)) or by disconnecting the battery for at least 30 sec., or better yet, a few minutes. After clearing the code, the compressor will run by jumping the low pressure switch connector allowing you to put freon in. After a few minutes, when the low pressure builds up enough (30-lbs or so), you can reconnect the plug to the low pressure switch and it will run as intended 'till you fill it all the way up (45lbs.). So don't forget to clear the code.