A/C Light Flashing

2007- A/C light flashing: I have searched and read many posts in the forum about this plus YouTube.
I changed out the Relay, checked In Cabin fuses, High and Low pressure are good, No Freon leaks.
Clutch and Compressor engages for 5-10 seconds then shuts off. Blows cold air..

I hot wired it at the main fuse box and can get the Clutch and Compressor to stay on. Blows Cold Air… Any other ideas? Thanks!

 

Update: I've replaced the air filter behind the glove box. Also, switched relays around and checked the new one to hear the click click of it opening and closing.
The garage I trust is backed up until end of Sept. 3 Toyota dealerships in Nashville so I guess I'll plan to go downtown and sit awhile unless there is something y'all know I am missing.

 

You need a good scanner (Techstream or other high end one) to read the codes in the AC Ecu (Amplifier). If the light is flashing its because it has a trouble code and the ECU will tell you why.

Seems most of your circuit it fine, just the AC ECU is disengaging the clutch for some reason. Until you read the codes you are really just guessing as to what its not happy about.
AC Pressure switch shutting you off? Lock Sensor? Something the AC ECU is reading in is making it not happy.

 

Thank You @Jeff_5_7! I have stumbled across YouTube videos showing how to run Toyota A/C Climate self diagnostic test. So far I'm seeing for Prius and Camry but thinking about trying it on Tundra. I hoping to have the "Duh, Big Red Truck" moment...

 

I know on 1st gens there is a ground wire on top of the compressor that the screw vibrates loose or the wire becomes broken.

Be wary of straight wiring the compressor,it can overheat and melt the wiring.

Sorry I’m not of much more help

 

So at this point y'all are laughing! Big Red Truck doesn't have a digital readout. 3 big knobs and 3 buttons. The A/C amplifier is located behind glove box so I'll just replace that. The air blows hard and cold when I jump it. Plenty of salvage yards around Nashville where I could replace a few other things as well.

 

When you say "jump it", I assume you mean jumping the relay to keep the clutch engaged all the time?

Truck will use a different AC amplifier depending on if you have digital readout or just the 3 analog knobs. Look at the part number on yours first. I wouldn't just jump to conclusions assuming your AC amp is bad. Possible yes, however not likely.

Seems to me the AC Amplifier is seeing an input that is telling it something is wrong. It then cuts the signal to the AC clutch relay to disengage the clutch, IE its way of turning the system off due to an issue.

I think it would be well worth your time to find someone with a diagnostic tool that can read the trouble codes from the AC Amplifer. I would think most Snap-On, Matco type high end readers can do it. I know Techstream can. I have also does it with the OBDFusion App and the added $15 Toyota Diagnostic package. Will need a Bluetooth OBD adapter for this.

Would hate for you to replace the AC Amplifier only to have it still do the exact same thing.

 

@Jeff_5_7 True. Yes I took a coated wire that I've stripped and jumped it at the relay. I know the relay is good cause I've tested it also and hear the click click. I've left the wire on just long enough to test the air speed and cold air.

Probably going to see how much work I can get out of Toyo Dealership with a diagnostic check all at one time. I'm having the dreaded intermittent 4LO flashing crank/no start issue too. No codes found at O'Reilly's.. 4WD works great after taking it to a friends rock quarry to test. I bang on the fuse box and other connectors to get the truck to start. It runs like a panther once started with no hesitation or noises.

I inherited the truck and his dog upon my younger brother's passing in January. I've pulled the Carfax to see all the service records previous to my brother's ownership. Toyota.com ownership page was garbage with that info.