Flickering Auto, A/c, Circulation Lights

[W-N]

I just noticed on my 2005 GX that the green indicator lights for the ventilation controls, specifically the A/C, Auto and circulation (recirc-fresh air) lights, flicker randomly. I only notice it at night and there does not appear to be anything that triggers it, just a random event each time. Has anyone else experienced this? Everything is functioning properly and the vehicle has been great, other than this one item.

[MarcP]

I just noticed on my 2005 GX that the green indicator lights for the ventilation controls, specifically the A/C, Auto and circulation (recirc-fresh air) lights, flicker randomly. I only notice it at night and there does not appear to be anything that triggers it, just a random event each time. Has anyone else experienced this? Everything is functioning properly and the vehicle has been great, other than this one item.

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I have been trying for months to find out if anyone else has this problem. Mine does the exact same thing - solar sensor is active (night mode) and the vehicle has to be moving - they don't flicker if you are sitting still. I also have Nav - do you?

[W-N]

I have been trying for months to find out if anyone else has this problem.  Mine does the exact same thing - solar sensor is active (night mode) and the vehicle has to be moving - they don't flicker if you are sitting still.  I also have Nav - do you?

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Yes. I have nav as well. I do not notice any other lights flickering.

[MarcP]

I have been trying for months to find out if anyone else has this problem.  Mine does the exact same thing - solar sensor is active (night mode) and the vehicle has to be moving - they don't flicker if you are sitting still.  I also have Nav - do you?

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Yes. I have nav as well. I do not notice any other lights flickering.

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I actually had the dealer look at it and replace the A/C panel (this is what Lexus suggested) and the problem got worse. I had them put my original panel back in and that is where things stand right now. The tech and I drove a few more GX's and all the ones with NAV seem to do this to some degree (mine is about middle of the road as far as how much/often it flickers) but the GX's without NAV are rock solid with no flickering. My feeling is that the electrical design of the systems with NAV are supplying a marginal voltage to the A/C panel indicators in the night mode and the LED's flicker - the incandescent illumination used everywhere else probably sees the same variation in voltage but doesn't react like an on/off LED will. Just my opinion...

[t28pilot]

Has anyone come up with a fix to this problem? I just purchased a 2008 GX470 that has the same problem.....

Thanks :)

Scott

[xxstewart]

I've notice the same problem on my 2008 GX. Actually, I think the entire design of the climate control system was the work of a moron. Has anyone noticed that in cold weather when you turn on the heater, the ventilation switches to suck in outside air, and in the summer when the vehicle interior is 120F+, it automatically switches to recirculate inside air? The GX is the only vehicle I've ever owned that has to be switched to defrost to get warm air onto the windshield, and when defrost is activated, the A/C kicks on and outside air is sucked in -- makes winter driving a !Removed!. The idea of having half the climate controls on the navigation screen and half on the dash button panel is ridiculous. Having to access the climate screen just to alter the fan speed is annoying. The owner's manual says the climate system can be voice controlled, but when I attempt this, I'm told the function is not available. The rest of the navigation system sucks too. The satellite radio song title truncates at 16 characters. I could write a book about the bugs and design goof-ups. I have the navigation screen set to return to the previous setting, rather than to always start with the map. This works except for after being in reverse gear -- the map always re-appears after backing up. I guess the designers thought if you backed up you missed your turn, and really need the map. I think the navigation/climate/entertainment system was designed by a bunch of software techs in Bangalore who've never driven a car. Better equipment is available standard on KIAs.

[kgerry]

I've got an 06 and mine does the same thing.... not too annoying, just an intermittent quirk......

[mann777]

The Flickering cause is the AC Magnetic Clutch relay, which is located in the Engine Bay Fuse Box. The flickering was effect to models between 2003-2006, Anyway I did not know the 2008 models were also affected. This could a remote case.Anyways Toyota issued a TSB to the same. The job is a 2 minute job. Also one needs to is replace the relay.

I am detail the inspection procedure.

1. Open the Engine Bay - Fuse Box.

2. Identify the AC Magnetic Relay( to locate use the map location on the inner cover of the fuse box)

3. Verify if this is the part number mentioned on the relay - If the part number is 90987--02022, please replace the relay with the countermeasured relay P/N 90987--02028.

4. The Vehicle should be without the Ignition Keys inserted.

5. If the new part number is what already installed in your vehicle, then only a diagnostic scan would tell you the problem.

The attached images are the Relay and the Relay location ( circled in red ) in the Fuse Box.

Last after replacement, disconnect the battery (-) termninal for 3 minutes and reconnect. And your are good to go.

Hope this helps.

[xxstewart]

The A/C magnetic clutch relay is an interesting diagnosis, and could well explain why the A/C indicator light flickers. But on my 2008 GX, all the light indicators on the climate control unit flicker -- even the rear defrost indicator. Flickering only occurs when the light brightness control rheostat (lower left of steering wheel next to 4WD switch) is set for dimming. When it's set to full brightness (past the tactile detent), the flickering stops. Flickering seems to affect the gear shift console indicators also, which is controlled by this rheostat. Are there any TSBs related to replacement of this dimmer control?

[caln]

The Flickering cause is the AC Magnetic Clutch relay, which is located in the Engine Bay Fuse Box. The flickering was effect to models between 2003-2006, Anyway I did not know the 2008 models were also affected. This could a remote case.Anyways Toyota issued a TSB to the same. The job is a 2 minute job. Also one needs to is replace the relay.

I am detail the inspection procedure.

1. Open the Engine Bay - Fuse Box.

2. Identify the AC Magnetic Relay( to locate use the map location on the inner cover of the fuse box)

3. Verify if this is the part number mentioned on the relay - If the part number is 90987--02022, please replace the relay with the countermeasured relay P/N 90987--02028.

4. The Vehicle should be without the Ignition Keys inserted.

5. If the new part number is what already installed in your vehicle, then only a diagnostic scan would tell you the problem.

The attached images are the Relay and the Relay location ( circled in red ) in the Fuse Box.

Last after replacement, disconnect the battery (-) termninal for 3 minutes and reconnect. And your are good to go.

Hope this helps.

Very good post, but the fuse box does not match mine. I am attach photos of mine. I cannot find a relay named "mag clch". One pic is of fuse box and small relay box behind. another is of the label on the underside of that small fuse box. The last is of the relay box on the left side of the engine bay with lid labels. Where is my "Magnetic clutch relay"?

[LZMF1]

Very good post, but the fuse box does not match mine. I am attach photos of mine. I cannot find a relay named "mag clch". One pic is of fuse box and small relay box behind. another is of the label on the underside of that small fuse box. The last is of the relay box on the left side of the engine bay with lid labels. Where is my "Magnetic clutch relay"?

man777 posted a pic of the engine bay fuse box in a GX470 which is what he and i have....you have a different model! you have an RX350, check the manual for the location(that's assuming your model has the same relay)....i'm sure you'll find it.

[mann777]

Yes, you seem to have a RX..and there was a TSB to that defect arising out of RX, I dont see your model, but the TSB was effective for 07 models RX and the solution was to replace the AC amplifier. The TSB is attached.

Hope the info helps

AC lite Blinking on RX.pdf

[Glenn in Texas]

I bought my '08 GX470 with 23,000 miles on it and a full warranty. I have the flickering issue as well. After many trips to the dealer, calls to Lexus, and a factory rep looking into it, the official response was that there is a known defect in the Denso Nav units. Lexus is looking into a fix, but most likely will not be able to address this. Since it is not a safety issue, there is nothing else Lexus will do for this problem. This was my 5th (and most expensive) Lexus. Very disappointed that this "upgrade" was so badly engineered. I agree with others on this board that the functionality of this unit is lacking in basic common sense.

[Trixtek]

I am an original owner of a 2008 GX470 and it has the same flickering lights issue described here. Combined with the practically useless voice recognition system, the failed satellite receiver ($700 to replace a radio part??? Not on my watch!), the poor AM radio quality, the weak antenna reception, and the convoluted spare tire storage (try stabbing the crank at night on the side of a dark road), this will likely be my last Lexus. My wife just purchased a 2013 Ford F-150 pickup with the Microsoft SYNC navigation package and it blew me away with its far superior performance. A Ford!

I have tried to cut Lexus some slack but then I have to ask, "Why should I?" I paid top dollar for my GX470 and expected it to be a top quality vehicle. The one I got is not.