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Discussion Starter · #1 ·
2005 Highlander V6

The AC suction hose has a severe leak, right in the middle of the rubber section loop. Of course these aren't just hoses, there is form fitted metal tubing on each end. So what is a non-dealership (affordable) solution? After-market, repair? I live in Dallas so it seems there would be a hydraulic shop or something of that nature in a big city that would be able to put something together.

Secondly, the car is 17 years old so when it started leaking I assumed the compressor seals. As far as I know they might be. With refrigerant at $9 per 12 oz can, at what point do you bite the bullet? And what is the solution, rebuilt? Looks like it would be a bear to access and replace.
 

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イリジウム
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Texas temperature was in the news! As well as many parts of the country. Gotta have AC!

Try rockauto. UAC is about $26 plus shipping. Looks like people prefer the Four Seasons with the heart symbol (popular item) at 2x the price! I would just get the UAC then, better warranty (12 months) than Four Seasons 120 days.


You can call around local AC shops, see if they can vacuum the system, swap in the hose and recharge it. Or do a two-step - vacuum it so you can work on the system, bring it back later for them to recharge it. Before inflation it was about $100-120, not sure now.

You definitely should have a professional shop do a complete check just to be safe, in case it was something else. Fix it right, fix it once.

And use the 5% off discount code if you buy from rockauto, scroll to the newest post:
RockAuto Discount Code
 

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Discussion Starter · #4 ·
Firewall connections:

There are black plastic retainers at the firewall end of the refrigerant hoses. How are those removed? Looks like there are tiny slots where maybe a pin needs to be inserted.
Thanks.
 

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Nitrogen pressure test. Awesome! Are these the retainers you're talking about? Use the two ends of a paper clip and push back the spring clip inside. See YT video.

Not sure if you guys Nylog in the HVAC industry, but you might want to Blue Nylog all the o-rings you can access, and maybe change out the desiccant bag, $1.15/ea UAC, or $6.41 with header.


 

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Discussion Starter · #6 ·
Thanks for the good info, paper clip and Nylog. Most HVAC connections are silfos, silver solder, or maybe a copper/brass flare fitting. Prefer silfos. I haven't worked with any of the new modular systems but I bet they may use some similar o-ring connections. So I really appreciate that info. If not too hard to remove I may remove and bake the desiccant, but the system has never been negative pressure so I think it is moisture free.

Thanks again x 2.

JH
 

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Discussion Starter · #7 ·
Replaced hose, ran vacuum, started charging. Clutch does not engage though working before hose change out. I pressure washed the compressor where the suction hose connects before starting the swap and saw no way washing would hurt a two wire power connection. I get a green light on the dash A/C button but I noticed there was no RPM bump. It was 100+ outside and hotter under the hood so did not investigate much until I have some info for a logical approach.

That said where can one get a schematic or preferably a wiring diagram for a 2005 Highlander 3.3 V6?
 

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2007 Highlander Sport 4wd 3.3 V6
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Replaced hose, ran vacuum, started charging. Clutch does not engage though working before hose change out. I pressure washed the compressor where the suction hose connects before starting the swap and saw no way washing would hurt a two wire power connection. I get a green light on the dash A/C button but I noticed there was no RPM bump. It was 100+ outside and hotter under the hood so did not investigate much until I have some info for a logical approach.

That said where can one get a schematic or preferably a wiring diagram for a 2005 Highlander 3.3 V6?
I know it may be too simple of a solution, but double check the electrical connector on the compressor. You also will need to ensure that the AC system has charged to the proper pressure(25-30psi low side) without any other addition leaks before the AC compressor will start in most cases.

When recharging make sure the engine is running and the AC fan controls are max out and the temperature set to the coolest setting.
 

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Discussion Starter · #9 ·
Thanks for posting.

I would like to check the electrical connection at the compressor but I have 2-3 problems. One, it is a booger to get to and I cannot see how to release it. Two, I now see it is a 3 wire connector so not just a easy continuity check for the clutch coil or power supplied to it. Three, though hard to see there seems to be a small black cable in the area too. So If someone can reveal how the connector releases that would be a start.

I also cannot find a fuse/relay for the compressor in the fuse box listing.

Regarding other points:
I cannot charge to proper pressure with clutch disengaged but I have a dual manifold and both sides are at 100 PSI plus. (Both sides will settle to ambient vapor pressure when the compressor is not running). So it should not be going out on low pressure. (Best I can tell there is a combo low/high sensor in the liquid line.)

Engine was on, green light on dash.

Regarding max settings, max fan is OK, on some systems MAX is synonymous with recirculate. I prefer to not recirculate but have doors or windows open and force the system to bust ass rather than pull in partially cooled air from the floor space.

Just as a point of reference or maybe "interesting but useless information" this system does not have a electronic thermostat. So the temp control only controls the warm air damper. In most automotive cases (especially this old) the clutch/compressor is controlled by a bang/bang temp sensor on the evaporator that keeps the evaporator between 35-40 degrees and the cabin air temp is more controlled by fan speed, recirc/fresh, and warm air mix; not terribly efficient. However, I bet electric vehicles have a much more efficient design to stretch miles per charge. Sure can't see them wasting watts generating hot air. Like most stuff you read on the internet, my info may be dated.

But I hope it is not as bad as 90% of the youtube experts explaining how to charge an A/C system. Ever notice how all the millennial youtube experts have brand new tools and brand new Home Depot 5 gallon buckets? All my buckets have traces of latex, mortar, thin set, grout, cement, or hypertufa in them. Never bought a 5 gal bucket in my 68 years on this planet, some of the older ones were metal.

Again, thanks for taking time to help.

TMI, message ends.
 

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Thanks for posting.

I would like to check the electrical connection at the compressor but I have 2-3 problems. One, it is a booger to get to and I cannot see how to release it. Two, I now see it is a 3 wire connector so not just a easy continuity check for the clutch coil or power supplied to it. Three, though hard to see there seems to be a small black cable in the area too. So If someone can reveal how the connector releases that would be a start.

I also cannot find a fuse/relay for the compressor in the fuse box listing.

Regarding other points:
I cannot charge to proper pressure with clutch disengaged but I have a dual manifold and both sides are at 100 PSI plus. (Both sides will settle to ambient vapor pressure when the compressor is not running). So it should not be going out on low pressure. (Best I can tell there is a combo low/high sensor in the liquid line.)

Engine was on, green light on dash.

Regarding max settings, max fan is OK, on some systems MAX is synonymous with recirculate. I prefer to not recirculate but have doors or windows open and force the system to bust ass rather than pull in partially cooled air from the floor space.

Just as a point of reference or maybe "interesting but useless information" this system does not have a electronic thermostat. So the temp control only controls the warm air damper. In most automotive cases (especially this old) the clutch/compressor is controlled by a bang/bang temp sensor on the evaporator that keeps the evaporator between 35-40 degrees and the cabin air temp is more controlled by fan speed, recirc/fresh, and warm air mix; not terribly efficient. However, I bet electric vehicles have a much more efficient design to stretch miles per charge. Sure can't see them wasting watts generating hot air. Like most stuff you read on the internet, my info may be dated.

But I hope it is not as bad as 90% of the youtube experts explaining how to charge an A/C system. Ever notice how all the millennial youtube experts have brand new tools and brand new Home Depot 5 gallon buckets? All my buckets have traces of latex, mortar, thin set, grout, cement, or hypertufa in them. Never bought a 5 gal bucket in my 68 years on this planet, some of the older ones were metal.

Again, thanks for taking time to help.

TMI, message ends.
Well there you go. The system is over filled. The compressor will not start with the low side at 100psi. You will need to get the low side down to about 30psi.

AC compressors tend not to work when the pressure is too low or too high than it is designed for. General the low side rarely need to go over 50psi in a automotive system. The Highlander is supposed to be about 30-32psi on the low side on a properly charged system(which varies with ambient air temperature).
 

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Discussion Starter · #11 · (Edited)
Thanks for posting but your reasoning is based upon a running system under ideal conditions.
The over pressure cutout is based on the liquid line pressure not suction line. The suction line and liquid line pressures equalize when the system off. Since it is 101 degrees my high and low side pressures were both reading about 126, which is the vapor pressure that should be read when there is vapor in the presence of liquid refrigerant. If there is no liquid you cannot depend on the TP chart.

I charge my system under full load; fan on high, recirc/max off, doors and windows open, and a high outdoor ambient. My suction pressure started at 60 PSI, which was darn good because that means the evaporator was running at 62 degrees even though the cab temp was 90+. My high side pressure is about 200, which tells me my condenser is condensing at ambient plus 30 degrees, subcooling will be a good bit lower.

I haven't strapped on temp probes yet to check superheat and subcooling but my 25 years of HVAC experience, cold suction line, finger burning liquid line, what the gauges tell me about what is going on inside the system, and the darn cold air coming out of the vents tells me I am in the ballpark.

When the cab temp gets down to normal and the evaporator is running between 35 and 40 degrees I am sure the suction pressure will be 30-35 PSI, but the high side will only drop a little due to ambient.

So the system was not overfilled but needed about 15 more ounces. The problem was electrical.

So there you go, amigo.
 

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2007 Highlander Sport 4wd 3.3 V6
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Thanks for posting but your reasoning is based upon a running system under ideal conditions.
The over pressure cutout is based on the liquid line pressure not suction line. The suction line and liquid line pressures equalize when the system off. Since it is 101 degrees my high and low side pressures were both reading about 126, which is the vapor pressure that should be read when there is vapor in the presence of liquid refrigerant. If there is no liquid you cannot depend on the TP chart.

I charge my system under full load; fan on high, recirc/max off, doors and windows open, and a high outdoor ambient. My suction pressure started at 60 PSI, which was darn good because that means the evaporator was running at 62 degrees even though the cab temp was 90+. My high side pressure is about 200, which tells me my condenser is condensing at ambient plus 30 degrees, subcooling will be a good bit lower.

I haven't strapped on temp probes yet to check superheat and subcooling but my 25 years of HVAC experience, cold suction line, finger burning liquid line, what the gauges tell me about what is going on inside the system, and the darn cold air coming out of the vents tells me I am in the ballpark.

When the cab temp gets down to normal and the evaporator is running between 35 and 40 degrees I am sure the suction pressure will be 30-35 PSI, but the high side will only drop a little due to ambient.

So the system was not overfilled but needed about 15 more ounces. The problem was electrical.

So there you go, amigo.
So you got cool air flowing out the vents without the compressor running?
 

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As I previously stated, the problem was electrical.
So you sorted out the problem? I was thinking that your compressor still did not turn on after you recharged the system. The pressure seems a bit high for the low pressure side;hence why I thinking that the system may have been over charged which prevented the compressor from starting.

Well, either way you seem to know what you are doing if you have 25 years of HVAC experience; so good luck.:)
 
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