AC Question

Hi there, Toyota has a TSB on a relay issue .
Not sure if you checked this?
My 2003 had a relay problem and the would work intermittently .
Relay turns compressor on. I put 1 in from a corolla and worked fine for a few years.
 
[MENTION=706150]jwkiss0[/MENTION] There will be a temperature difference inlet to outlet side of HCV when closed.
If not, HCV has internal issue. I/R temp gun a handy gizmo.

The lines running in and out of the HCV all feel hot. Does this mean it’s faulty? Do I need a temp gun to see how close they are in temperature or should they feel different?
 
The lines running in and out of the HCV all feel hot. Does this mean it’s faulty? Do I need a temp gun to see how close they are in temperature or should they feel different?

Just checked mine had 20-25* temp difference it not ideal troubleshooting at HCV due to heat sink.
Borrow one wouldn't buy one unless you just want too. FSM say's this pg. AC-63.

WATER VALVE ON-VEHICLE INSPECTION
1. WARM UP ENGINE
2. DISCONNECT WATER VALVE CONTROL CABLE
3. INSPECT WATER VALVE OPERATION
(a) Check that warm air blown out the vent when the water valve lever is moved to ”WARM” position.
(b) Check that cool air blown out when the water valve is moved to the ”COOL” position.
If operation is not as specified, replace the water valve.
4. CONNECT WATER VALVE CONTROL CABLE
 
Another quicky thing to check is the compressor clutch activation/solenoid.
- Just like checking the HCV, cycle the control between hot/cold.
- When set to cold, you should see the clutch engage the AC compressor on the engine.
- When set to hot, it should release.

Having said that, I've never looked at mine, and I'm not at my car right now. But, from experience on other cars, it goes like this:
- The AC compressor is run by a pulley/belt off the engine crank. (Engine front, lower, passenger side)
- Coaxial with, just in front of, the AC pulley is the AC clutch mechanism.
- When engaged, the clutch will compress against the pulley and engage the AC compressor.
- When disengaged, the clutch will release and spin independently of the pulley.
- The state of engaged/disengaged can be seen by watching that clutch plate.

These are just diagnostic steps before you start swapping parts or taking stuff apart.
 
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a.c. clutch

hello i have an a.c. poblem on 2000 4 run ive tried everything ive read or watched except jumping from the low pressure relay behind glove box how is this done or is it worth it? just need clutch to enguage any info will be highly appreciated.
 
As mentioned earlier in this thread, I would suspect either the control unit, or the HCV actuator, cable, or valve.
Pretty easy to check the HCV system. Cycle between hot/cold as you mention, and see if the HCV opens/closes consistently. You can look at the HCV on the engine bay firewall, or look at the actuator in the rear left corner of the passenger footwell.

If the OP or anyone decides go for a climate control module rebuild, skip the $200 eBay guy - there is a guy on this forum, John Hadfield, in NJ who does (did) it for $63 including return shipping. Add $10 if you want new LED in diff colors.

Below is what he sent me about 6 months ago. My unit had lost its damn mind and did whatever it wanted to do. I got it back fast and it has been working flawlessly. The units are not hard to repair yourself if you can solder and know where the weak points on the circuit board are, but I was happy to have him do it while I worried about other stuff I've got going on....

"Right now, I am doing the repair for $63 which includes return shipping.
Shipping (TO John) usually around $10 to $15. If you would like a different method of return shipping just let me know.
If you want an LED upgrade, that's $10 more. Colors for the LEDs are
White, Blue, Red, Amber and Green and OE Green and ice blue. I have
examples of these colors if needed "
 
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If the OP or anyone decides go for a climate control module rebuild, skip the $200 eBay guy - there is a guy on this forum, John Hadfield, in NJ who does (did) it for $63 including return shipping. Add $10 if you want new LED in diff colors.

Below is what he sent me about 6 months ago. My unit had lost its damn mind and did whatever it wanted to do. I got it back fast and it has been working flawlessly. The units are not hard to repair yourself if you can solder and know where the weak points on the circuit board are, but I was happy to have him do it while I worried about other stuff I've got going on....

"Right now, I am doing the repair for $63 which includes return shipping.
Shipping (TO John) usually around $10 to $15. If you would like a different method of return shipping just let me know.
If you want an LED upgrade, that's $10 more. Colors for the LEDs are
White, Blue, Red, Amber and Green and OE Green and ice blue. I have
examples of these colors if needed "
I have figured out that I have to constantly cycle the temp knob between hot and cold to get it to work. I am assuming I need to send it to the guy in NJ to rebuild.Thanks for the heads up.
 
I am looking for a factory service manual for 1999 Toyota 4Runner and I am wondering where did you get the page that is designated with AC-99? I have tried to look for a paper copy of the A/C system on ebay to no avail. The real reason I want the book is to see how much ND-8 oil the whole system holds. I am replacing everything in the system, I just want to know what the total capacity is for the whole system so I don't overfill it. If you can help, I would greatly appreciate it.
 

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