Flashing A/C Light (1 Viewer)

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

@vcheng : Not to my knowledge. Yesterday they did say I had good levels of refrigerant (don't think they had to put any in) but there was no mention of the drier cartridge replacement at all. Again, hoping this little relay replacement solves the problem, if not it may be back into the shop.
 
@vcheng : Not to my knowledge. Yesterday they did say I had good levels of refrigerant (don't think they had to put any in) but there was no mention of the drier cartridge replacement at all. Again, hoping this little relay replacement solves the problem, if not it may be back into the shop.

Consider replacing that at some point anyway. It can lose hygroscopic efficiency and even burst with age to cause many avoidable issues.
 
Update: Relay replacement worked like a charm, everything is back to normal. Hopefully this will save others some time, it's an easy cheap thing to try first and see if it solves the issue like it did for me.
 
It was the RPS sensor that is built into the compressor that was putting out a dirty wave form and causing the the compressor to disengage. Which throws the blinking light.
 
@spaber05 , you replaced the C/opn relay and that fixed your AC? the mg clt is the ac clutch relay and it is on the underside of the main fuse box. The TSB was for the ac clutch.
I just wanted to check so if that happens to me I could try the c/opn relay, which doesn't make sense because that's part of the fuel system. We have the same year LC
 
@jerryb - Initially it fixed the issue, yes, because the A/C light stopped flashing and the air blew cold again.

But now I have a corroded rear AC line that is needing some help and although it is spliced, my mechanic is running into more difficulty that we have yet to solve (compressor not kicking on despite pushing button and having Freon in it).

What is the story with the fuse under the main fuse box? I'd love to learn more about this because from what I found there is nothing under our fuse box, only in the LX.
 
I'm sorry to say that the LX and LC are the same, 2003-2007.
pdf with c opn, front ac wiring and underside relays attached. That's from the 2004 book, but the 06 book is the same for this. This thread was posted before with pics. 2005 LX470 Main Junction Block Replacement
 

Attachments

  • relay, mgt, copn.pdf
    341.1 KB · Views: 127
Thanks @jerryb, I'm still going to remain optimistic as my mechanic has diagnosed it has a faulty compressor and is replacing it as we speak. He said he hotwired it and the clutch did not engage so that seemed like a pretty obvious answer to me.

It's odd then that the replacement of the C/OPN relay solved my issue earlier if that relay is not related to the A/C system.
 
I couldn't believe they put so many relays under there. I wouldn't wish that 500 dollar part swap on anyone.
 
Replaced with the updated part from Amazon $19. Will see if during summer it starts acting up.
Finally we got some high temps in NE area, so my AC did the flashing light on me yesterday. Which means non of the things that I have tried so fat worked for me.
A mechanic asked me to pull in to his garage that this happens, but yesterday he could not look at it :-(
So my next step would be to try research what @Nighthawk11 posted: "It was the RPS sensor that is built into the compressor that was putting out a dirty wave form and causing the the compressor to disengage. Which throws the blinking light."
 
Question.. mine only ever does this if I leave on the AC and turn the truck off. Sometimes, when it cranks with the system ON it will do this. Usually, leaving it off for a minute and turning it back on works fine. Could be a relay, I guess. Anyway, that's my experience.
 
As another poster noted, check your connections to the compressor. I was having the same issue. I replaced the MG CLT relay and was still blinking. I went thru the connections and pushed tighter and eureka, blinking light stopped and cool air blowing!
Can you tell us which of the connections did you re-seat?
 
I am going to re-connect all the electrical connections to the compressor tomorrow, as I have already replaced the compressor (with Denso), condenser, evap coils, relay (updated relay). If this does not work, I'm going to replace the solar sensor and ambient temp sensor- beyond this, I'm stumped. The only thing i can say is that when my low pressure port had a blowout of gas, there was 134a all over everything on the front of the motor, including the drive belt. I suppose the belt could be slipping under a certain RPM, as it only seems to happen when idling for a while (while parked) or in slow traffic where RPMs are low. Once I start driving, things seem OK, and it works fine. Old belt off/brake cleaner on the pulley, dry, replace with new belt. That is, *if* reconnecting/reseating the connector.
 
Replaced the relay with a new one from Toyota and that did not fix the problem.

The codes that it is throwing are not in the book:

Flashing Rear Defrost light & Rear A/C light

A/C comes on for 3 seconds with a solid A/C light - blows cold - and then auto-shuts off with the a Flashing A/C Light

Do we have any Certified-employed by Toyota Mechanics that could point me in the right direction? When you start pricing A/C components your jaw will hit the ground!
What did you you do to fix this issue? i have the exact same problem..
 
I had gthe exact same issue. Though the consdenser coil LOOKED ok from the outside- when it was removed, i saw the leak on the covered edges. It held pressure and everything, but was completely hosed- IN fact, just handling the thing to remove it, the fins flaked off like paper. After I replaced this, with a Denso part and re-charged the system, it's been ICE cold now for over a year. If you have rear AC, be sure to get the LARGER one built for Dual Air systems.
 

Users who are viewing this thread

Back
Top Bottom