Afs Light Blinking- How To Reset? Anyone?

[FZ6 Dude]

Hello Folks,

So, I made the unfortunate mistake of removing the nut off of the AFS sensor by the rear right tire, and now my light is blinking. (2006 RX330 AWD) I tried to get under the car and adjust exactly where the arm attached to the unit (not the other threaded end) while my wife stared at the light, but had mixed luck. If I hit that sweet spot just right, the light would go off, but then as I tightened it down, it would move ever so slightly, and go right back on.

Does anyone know if there is a special way to adjust these, or to just tighten the linkage down, and then "reset" the sensor from that point? I have a state inspection coming up, and the last thing I need is to have some guy fail me for a blinking light that he has no idea what it means.

Thanks in advance,

Dennis

[cduluk]

Hmm... you shouldn't be getting an error light flashing unless the sensor is "damaged" or shorting out, etc. Normally you should be able to move that swinging "arm" through its entire range without a problem.

Did the sensor get opened up or anything? If the interior workings of the switch are damaged that might cause the error lights to come on.

And you're talking about the "auto-leveling" switch, right? AFS is the system that turns the headlights left and right when you go around corners, while the auto-lleveling system moves the lights up and down. I'm guessing the car has the AFS light blinking for the auto-leveling system errors too.

In any event, the only way to fix the problem is to either replace or repair that switch. If you simply unplug the switch, the error light will still blink (removing the switch will make the car think it's damaged). I would remove the switch from the car and open it up (there are screws you can remove, it opens up very easily) and make sure all the contacts inside are normal. There may also be dirt inside that you can clean. The switch is actually not very complicated, and one you've got it open I'm sure you'll be able to get it working again.

And the position of the arm shouldn't make the error lights come on. So don't worry about calibration ;)

[FZ6 Dude]

Yes, its definetly the AFS switch. I cant understand how the contacts could get thrown off inside the switch from me simply removing the bolt from the unit, and then reattaching it, but I guess somehow it could be possible. I have not tried to turn the switch off and back on, but I guess that is an option too. I will try both of these, and if anyone else has experienced this too, please let me know what worked for you.

Thanks

Hmm... you shouldn't be getting an error light flashing unless the sensor is "damaged" or shorting out, etc. Normally you should be able to move that swinging "arm" through its entire range without a problem.

Did the sensor get opened up or anything? If the interior workings of the switch are damaged that might cause the error lights to come on.

And you're talking about the "auto-leveling" switch, right? AFS is the system that turns the headlights left and right when you go around corners, while the auto-lleveling system moves the lights up and down. I'm guessing the car has the AFS light blinking for the auto-leveling system errors too.

In any event, the only way to fix the problem is to either replace or repair that switch. If you simply unplug the switch, the error light will still blink (removing the switch will make the car think it's damaged). I would remove the switch from the car and open it up (there are screws you can remove, it opens up very easily) and make sure all the contacts inside are normal. There may also be dirt inside that you can clean. The switch is actually not very complicated, and one you've got it open I'm sure you'll be able to get it working again.

And the position of the arm shouldn't make the error lights come on. So don't worry about calibration ;)

[cduluk]

Are you totally sure there's an "AFS" switch at the right rear wheel? I always thought the switch for "AFS" was within the steering column to detect deflection of the steering wheel left and right...

The only switch i know of at the right rear tire is that little one with the arms connecting the right rear control arm with the body of the car. This is for the auto-leveling of the headlights, not AFS. It detects when there's weight in the back seat of the car which would pitch the nose up, causing the headlights to blind oncoming drivers. When this switch detects movement in the control arm (when there's weight back there, weighing the back down) it sends a message to the headlights' auto-leveling motors to angle the headlights down so you don't blind oncoming drivers...

Since the 04-09 RX doesn't have an "auto-leveling" indicator on the dash like some older models, when there's an issue with the auto-leveling system the "AFS" indicator will blink instead.

What was your reasoning for touching the switch in the first place?

In any event, that's what the switch is... and i'd first try to remove the switch from the car and open it up to see if there's anything inside that might be causing a break in the circuit. These switches are prone to this and can often be repaired before having to be replaced. <_< I've done this myself, and on my old RX300 i removed the switch from underneath the car and wired it into the cockpit, and installed a "rolling" ball on it so i could raise and lower the headlights whenever i felt like it. It's simply a potentiometer...

See my old Rx300's cardomain page, about half way down; you can see the "roller" switch i made where the driver's knee would be.

http://www.cardomain.com/ride/3090724/2003-lexus-rx

[lemon]

Yes, that's the 'switch' he's talking about (maybe we should call it a 'sensor' instead). If that switch is defective or mal adjusted, it will light the AFS light in the dash.

FZ6 dude, I have the service manual at home and I remember seeing something about calibrating or initializing the AFS (vaguely remember - I could be mistaken). I'll check when I get home and post my findings. There should at least be instructions on installing the sensor at the rear wheel...mabye there's some special procedure.

[FZ6 Dude]

Thanks. That would be very helpful! The main reason that I think it is the AFS sensor is that it came on the very first time I turned on the car after having temporarily removed the arm. Also, I can adjust the arm location on the sensor slightly, and get it to go off, but not before I can tighten the nut down.

I imagine like anything else, calibrating it is probably a simple set of steps, that only Lexus is knowledgeable too, but if they put it in the repair manual, that would be awesome to know for us that like to do things ourselves.

[FZ6 Dude]

Got it! It was a matter of trial and error to find that "sweet spot" and tighten it into place. Thanks all for your help!

[cduluk]

[lemon]

I was just about to post this. In the service manual, it didn't show any special procedure for bolting the sensor on. But I did find this, and don't know if it would have helped or not...

____________________________________________

Engine is running and shift range is in the P position.

Press the AFS OFF switch eight times at approximately one-second interval (once for ON and once more for OFF, i.e. 4 times ON and 4 times OFF).

HINT:

The AFS OFF indicator light starts to blink twice per second.

Initialization can be started when the AFS OFF switch is either in the "ON" or "OFF" position.

When the AFS OFF switch is pressed eight times, it will return to its original state.

NEXT

2.INITIALIZATION OF AFS ECU

Turn the steering wheel to adjust the tires so that they point straight ahead.

Do not change the steering wheel position. Press the AFS OFF switch twice (once ON and once OFF).

HINT:

The AFS OFF indicator light stays lit for two seconds.

When the AFS OFF switch is pressed twice, it will return to its original state.

Do not change the steering wheel position and press the AFS OFF switch twice within 3 to 10 seconds.

HINT:

The AFS OFF indicator light stays lit for two seconds.

When the AFS OFF switch is pressed twice, it will return to its original state.

Do not change the steering wheel position and press the AFS OFF switch twice again within 3 to 10 seconds.

NEXT

3.CHECK COMPLETION OF AFS ECU INITIALIZATION

When the initialization of the steering sensor signal is completed normally, the AFS OFF indicator light goes off, comes on, or blinks depending on the specific condition 3 second after the indicator light goes off.

Result:

Proceed to

Result

A

Goes off: Initialization is started with the AFS OFF switch OFF (not pressed)

Comes on: Initialization is started with the AFS OFF switch ON (pressed)

B

Blinks: Blinks twice per second

HINT:

Failure to complete initialization. Proceed to step 2 within 10 seconds.

If 10 seconds elapse, the system starts steering neutral point automatic correction.

[PeterLexusRX300]

Thanks, this worked and reset my blinking light. System now fully operational again