2002 A/C issues and HVAC control unit diagnostics.....

Anyone have experience diagnosing the control unit or a link to a Toyota repair manual diagnostics for it?

Having a/c issues on my 2002 and have determined neither the blend door or compressor/ charge are the issue. Typical cold/hot knob back and forth did the trick for close to a year but no so much anymore. Original Denso compressor clutch was changed 15-20k miles ago and cycles/ engages as it should. Recently replaced the blend door with a Dorman unit and nothing changed. While plugged in (but not bolted in place) verified my original Denso blend door works as it should. Moved blend door arm manually and although a bit stiff it moves fully through it's range and does change the cold/ hot air selection properly. Only thing left to check would be the control unit it self....

Recently on a trip I experienced 105-110F outside temps and the a/c could not keep up. It did get much cooler while highway driving at 65-70mph but never got "ice cold" even with blower on max setting. This lead me to closely inspect the condenser which is not restricted in any way and all the blades are intact. Next i looked at the fan clutch (replaced 20k miles ago with an aftermarket unit). It seems to work fine and stops within 1/2 turn after spinning it by hand while the engine is off, engine temp gauge is always stuck a hair above the middle at operating temps. Either way I'll be replacing it with the

$89 AISIN FCT-013 Engine Cooling Fan Clutch - Compatible with Select Toyota 4Runner, T100, Tacoma, Tundra

AISIN FCT-013 just to be sure.

much appreciate any input!

 

for the HVAC control panel.....go used $50-$85

you have your rad/fan shroud present?

 

Regarding engine temp, when’s the last time you replaced the radiator cap?
I clean mine a couple times a year then just replace it after a couple years.

 

Truck got a brand New Koyorad radiator, OEM rad cap, OEM rad hoses, AISIN water pump, OEM TStat and so forth. No engine cooling issues what so ever.

A/C finally took a real shit. Even moving the cold/hot temp back and forth now does nothing. Got in the AISIN heavy duty fan clutch and have a brand new OEM HVAC control unit on the way. Wasn't about to take the chance on used or aftermarket units on this and the New unit from McGeorge yota parts was only $150 bucks. Will update once parts are installed.

 

What are your opinions on that radiator? Good fit/quality? And which model did you go with?

 

Excellent experience with the koyorad. Got it from Rockauto and don't remember the exact part# but it's been in the truck for 2-3 years and has given me zero issues.

 

All aluminum one or plastic tank?

 

2 or 3 row?

 

Big difference between the aisin clutch and the "heavy duty" Amazon clutch i had in there. barely spins by hand....