Flashing AC sign (1 Viewer)

Joined
May 20, 2020
Messages
21
Location
LEX KY
Howdy.

I had my AC compressor & condenser replaced on my 03' Land cruiser over the past week. The replacement worked to some extent as I was able to get cold air to blow when I hit the auto button when I started the car. It worked best when I had RPM's moving but it would blow hot air when I would slow down at a stop sign or in traffic. I could keep going back and hitting the AC button to get it to blow cold air but it would flash off after 10-15 seconds. Ill note that the freon or what ever was flushed out and refilled. Not a mechanic so forgive me on the wording, but I know the freon part was taken care of.

My light is still blinking, and I took it to another guy to get a second opinion. He thinks it may be a relay issue. I am taking the car back over this week to him so he can trouble shoot it further, but I wanted to see if anyone had any insight on this.

Feedback would be great.

Thanks!
 
Joined
May 20, 2020
Messages
21
Location
LEX KY
I'd be taking it back to the first guy, sounds like he didn't do the job right. Check the AC clutch and the sensor on it.

Thanks for the feedback. 2 Quick questions if you don't mind.

1. From what I shared can you tell me a little more on what signals he didn't do the job right? Just so I have a better basis of understanding.
2. Additionally so I can better understand, can you tell me what AC Clutch & sensor would show if it wasn't done correctly?

I really appreciate the feedback as I am not well versed in the mechanic side of things.
 
Joined
Apr 27, 2003
Messages
9,776
Location
Salt Lake City
What led you to replacing the AC compressor and condenser in the first place? Was the AC light blinking before that? Why take it to someone else if the first one didn't fix it?
 
Joined
May 20, 2020
Messages
21
Location
LEX KY
What led you to replacing the AC compressor and condenser in the first place? Was the AC light blinking before that? Why take it to someone else if the first one didn't fix it?

Thanks for getting back. Ill keep it as top level as I can.

1. AC was not blowing cold air so I took it to the first guy to look at it. He determined the compressor & condenser needed to be replaced, im not an expert but I can certainly ask to get that detail as it seems you may have some insight.
2. Yes the AC light was blinking on and off before then which made me think there may an electrical issue as well.
3. I am taking it to a second person since the guy who put the compressor in couldn't fix it all the way as he couldn't figure it out. I have only paid for parts so he told me to deduct out what ever I pay the second shop (that successfully fixes it) from the remainder I owe him.
 

saucebox

Slobivius Americanus
Joined
Jan 24, 2009
Messages
2,189
Location
SLC, UT
It could be the relay, but either of those shops should be able to diagnose why you're not getting cold air consistently.

I had the relay problem years ago. It was in a 4Runner (still the 2UZ), and it was about $25 for a new one. IIRC it's more difficult to replace in the 100 series.

Edit: this thread has more info, including links to even more threads discussing the relay. AC magnetic clutch relay location on 2003 LX470
 
Joined
Apr 27, 2003
Messages
9,776
Location
Salt Lake City
The light flashing means a diagnostic problem. Before replacing things a good shop should walk through a process of checking what's wrong. Without knowing more your situation could be a simple sensor, a relay as mentioned, or the clutch. Did they use new OEM parts? What led the first guy to think both the compressor as well as the condenser needed to be replaced, other than no cold air.
 
Joined
May 20, 2020
Messages
21
Location
LEX KY
It could be the relay, but either of those shops should be able to diagnose why you're not getting cold air consistently.

I had the relay problem years ago. It was in a 4Runner (still the 2UZ), and it was about $25 for a new one. IIRC it's more difficult to replace in the 100 series.

Edit: this thread has more info, including links to even more threads discussing the relay. AC magnetic clutch relay location on 2003 LX470

Thanks for providing this. I think this may be the route I will have to go.
 
Joined
Oct 23, 2019
Messages
384
Location
Western Australia
By screwed you mean installed and/or the part was faulty?
These systems do not break easily, they are built for time.

- Confirm the right parts were used. Compressor/condensor. (Why wasn't the dryer bag replaced? Why wasn't the system checked for leaks ffirst)
- Get confirmation that it holds pressure. Fridge systems act weird when there is a problem with gas cycling , .i.e. not enough gas or even like a home appliance fridge laid down on side. But for a car I would think merely about not enough gas in system, since the system can not be moved.
If the above are both right:
- Check what ppl said above. relay/sensors

However, what you are describing from my understanding of car A/C systems, relates directly to leaks in the system. Once the gas is holding pressure you should see the temps go down. Actually, with the AC light going off, def sounds like could be malfunction in a part. Fingers crossed for you its not an incorrect part.
 
Last edited:
Joined
Oct 23, 2007
Messages
116
Location
Lagos state - Nigeria
Thanks for the feedback. 2 Quick questions if you don't mind.

1. From what I shared can you tell me a little more on what signals he didn't do the job right? Just so I have a better basis of understanding.
2. Additionally so I can better understand, can you tell me what AC Clutch & sensor would show if it wasn't done correctly?

I really appreciate the feedback as I am not well versed in the mechanic side of things.
The compressor has an issue that's why the ac light is blinking. I have gotten the same problem before with my ac until I replaced my compressor with a new one the issue is solved and I have been having cold air since then.
 
Joined
May 28, 2020
Messages
1
Location
Las Vegas
Just pick up my new 99 LX470, when I drove home notice AC not cold, call back to the seller is machines shop got it from Auction ( he fix n flip, friend of mine) and said top up the Freon already. Next day AC work light stay on but kinda weak air coming out, Turn off AC and turn back on, LED light is blinking. Swap the AC Magnet Clutch Relay (MG CLT) with Heater Relay (MIR HTR) at front fuse box, work fine for a day. If I turn off AC and turn on it’s keep flashing. I watch a YouTube video said itused same ground.
When AC work it’s about 63°F at the vent front and 68°F at the back.
possibility advice:
1. Change both MG CLT & MIR HTR relay, can I use new after market China brand relay?
2. Blower resister issue. Its turn different speed from level 1-5 but weak air output. It’s sound turning very fast.
3. Actuator not completely close.
want DIY route instead breaking the bank.
Thanks
 
Joined
May 20, 2020
Messages
21
Location
LEX KY
Just an update, I am still working through these issues.

Ill keep you posted.

Thanks for the help
 
Joined
Jul 26, 2019
Messages
198
Location
North Carolina
Had Similar issue, when it would work AC was ice cold then would go out. I could restart AC and sometime it would work. There are several threads on this issue, but mine was something else. Somehow the compressor connection was loose. Couldn’t believe it when mechanic told me that, felt like an idiot.
 
Joined
May 20, 2020
Messages
21
Location
LEX KY
Thought id give an update:

After refilling with more freon, the ac was working at a short term acceptable level. Ill note that the ECU was not reset after getting freon put in. Anyway, short term acceptable level -> front was blowing cold on Re-circ when driving, and occasionally at stops it would blink on the dash and then turn off, but I could keep turning it on and it worked. Then I went on vacation for 6 days and came back to the front blower not working. yikes.

Ill call out that the blower did come on 3 times, and all seem to be when I was elevated or facing down hill. So it was back to the short term acceptable level, but now it wont turn on at all.

I am getting cold air in the front when I am driving long distances & the air is on "fresh" rather than re-circ mode or what ever. Rear blower does work and seems to be blowing cold when driving and not, but haven't really tried sitting while in Re-Circ mode.

Anyway, the guy who was looking at this for me basically through in the towel and realized he couldn't figure it out. He finally pointed to the best bet being a junction box replacement which seems inevitable as it was in the original quote from another servicer before this circus. Winter is coming (lol), and I hope to be able to have heat blowing in my Car during the cold mornings and nights. But first, Its still hot as hell so consistent AC would be nice.

So thats where I stand. Any insight on this or should I just bite the bullet and get the junction box replaced?
 

BadReligion

SILVER Star
Joined
Aug 23, 2011
Messages
782
Location
Reno, NV
If you think all of the mechanical components of the AC system are working fine, it could very well be the relay. Your issue sounds electrical to me. A few people have taken the junction box apart and you can get to the AC relays but I have not been able to find replacements by searching the #s on the OEM Denso relays. You would have to desolder the old ones and solder in the new ones but thats not complicated. That would be a $5 fix compared to $600 for a new junction box.
 

Users who are viewing this thread

Top Bottom