A/C quick question (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Dec 13, 2012
Threads
123
Messages
1,129
Location
Meridian Idaho
Is it normal that my LX450 A/C compressor clutch engaged all the time then it is ON ? what part or relay controls stitching
TY
 
On call for AC the compressor clutch engages the pulley yes. On NA trucks the AC button turns it on. On JDM trucks the temperature control module does it. AFAIK...
 
On call for AC the compressor clutch engages the pulley yes. On NA trucks the AC button turns it on. On JDM trucks the temperature control module does it. AFAIK...
yes AC compressor is running and blowing cold but running all the time with no intermittent OFF/ON switching, in MY LC100 I can see how pulley start and stops , but in LX450 it is spinning all the time
 
So button marked "AC" on the tmp control panel is in off but AC pulley still engaged. Hmmm. There's a 2 wire connector on the clutch. Pull that off and it disengages. Test that for a short. Otherwise its the clutch itself.
 
So button marked "AC" on the tmp control panel is in off but AC pulley still engaged. Hmmm. There's a 2 wire connector on the clutch. Pull that off and it disengages. Test that for a short. Otherwise its the clutch itself.
no not like that
 
To clarify, the compressor engages when the A/C switch is turned on and does not cycle on/off during operation. Only cycles off when the A/C switch is turned off?
 
To clarify, the compressor engages when the A/C switch is turned on and does not cycle on/off during operation. Only cycles off when the A/C switch is turned off?
Yes that is it, it is constantly working and overheating radiator
 
Yes that is it, it is constantly working and overheating radiator


hello Peter ,

- a constantly running or engaged compressor clutch in the ON mode 100% of the time should not be the sole or only cause of your overheating issues ?


- in fact it should NOT even ever cause a engine high TEMP. gauge spike at all ?


- the Engines thermostat will sense and detect a ever hotter becoming coolant and continue to mechanically OPEN up more and more as needed to allow more coolant

flow throughout your cooling system .........


- i would suggest looking outside the TEq Box here maybe , confirm and verify both your coolant temp sender / sensor , and also more importantly , your Coolang guage in the cluster meter per the FSM step by steps stand alone bench tests .....



- thermostat replacement i am sure you have done by now if you know my SOLID MUD Buddy Peter the Great ........ :) 🍻
 
hello Peter ,

- a constantly running or engaged compressor clutch in the ON mode 100% of the time should not be the sole or only cause of your overheating issues ?


- in fact it should NOT even ever cause a engine high TEMP. gauge spike at all ?


- the Engines thermostat will sense and detect a ever hotter becoming coolant and continue to mechanically OPEN up more and more as needed to allow more coolant

flow throughout your cooling system .........


- i would suggest looking outside the TEq Box here maybe , confirm and verify both your coolant temp sender / sensor , and also more importantly , your Coolang guage in the cluster meter per the FSM step by steps stand alone bench tests .....



- thermostat replacement i am sure you have done by now if you know my SOLID MUD Buddy Peter the Great ........ :) 🍻
o we know it is A/C doing so is is heating A/C radiator to sizzling temperature
 
o we know it is A/C doing so is is heating A/C radiator to sizzling temperature

What's the ambient temperature when this is happening?

The first thing you should do is get AC gauges on there and see what your high and low side pressures are. See what they are at idle, and at 1500 RPM. Warm the engine up before checking the pressures.

(Edit: temperatures ==> pressures, stupid brain)
 
Last edited:
To clarify, the compressor engages when the A/C switch is turned on and does not cycle on/off during operation. Only cycles off when the A/C switch is turned off?

I was under the thought that if you were in some overheat-mode (no clue parameter) - between the 2 temp senders in a 1FZ that it would kick out the compressor & go into a ‘limp mode’.

Was I especially stupid on this?

I swear it was old content, maybe early Mud or late Spectre board…… :meh:
 
The compressor is supposed to cut out when the coolant temp hits ~226 F and back on at ~217 F.
 
The compressor is supposed to cut out when the coolant temp hits ~226 F and back on at ~217 F.

Thank you.

I thought I knew that, but blind squirrels, yadda.

-I’ll tempt fate - is that based off the 1 of the temp senders like I thought, or some other reader?
 
"Engine coolant temperature cut switch".
 
"Engine coolant temperature cut switch".
I’m going to flip pgs in my EWD book tomorrow, this will get a sticky-tape tab.
Just for future knowledge. ;)
 
What's the ambient temperature when this is happening?

The first thing you should do is get AC gauges on there and see what your high and low side pressures are. See what they are at idle, and at 1500 RPM. Warm the engine up before checking the pressures.

(Edit: temperatures ==> pressures, stupid brain)
Bingo! Don't blame the compressor for the overheating issue, it could be a different problem.
 
The compressor is supposed to cut out when the coolant temp hits ~226 F and back on at ~217 F.
yes that only emergency cut off, I am talking about normal A/C functionality compressor can not be on all the time, it needs to cycle
 

Users who are viewing this thread

Back
Top Bottom