Self-levelling Headlamp Fault

aspire · December 9, 2009

My 2002 SC430 has been maintained by an independent garage rather than the dealer, for a while, but I went back to ask about my self-levelling headlamp problem, and it is not a job they are equipped to deal with.

The warning light on the dash comes on intermittently, and even when it is not on, sometimes the lights seem to be "hunting" up and down for the correct position.

I could return to the Lexus dealer, but my garage recommended a local auto-electrician "as long as they are motorised, rather than pump operated."

Can someone advise if they are motorised or pump-operated? Any other thoughts on the subject also welcome - including any experience of the cost of repair.

Derek

steve2006 · December 9, 2009

Hi,

I had a look on www.toyodiy.com and the headlight adjustment is electrical as they have motors fitted.

85661 MOTOR, HEADLAMP LEVELING, RH

85661‑50040 UZZ40 1 € 108.93

85662 MOTOR, HEADLAMP LEVELING, LH

85661‑50040 UZZ40 1 € 108.93

85669 PACKING, HEADLAMP LEVELING MOTOR BASE

90075‑99120 UZZ40 2 € 3.38

I don't know about the SC430 but there have been problems with the suspension height sensors on the later LS models which may be something associated with the headlamp malfunction.

lizzy borden · December 11, 2009

My 2002 SC430 has been maintained by an independent garage rather than the dealer, for a while, but I went back to ask about my self-levelling headlamp problem, and it is not a job they are equipped to deal with.
The warning light on the dash comes on intermittently, and even when it is not on, sometimes the lights seem to be "hunting" up and down for the correct position.

I could return to the Lexus dealer, but my garage recommended a local auto-electrician "as long as they are motorised, rather than pump operated."

Can someone advise if they are motorised or pump-operated? Any other thoughts on the subject also welcome - including any experience of the cost of repair.

Derek

They are on motors.

It's probably the sensor on the back axle.

It's easy to diagnose. jack the car up and remove the sensor but leave it plugged in. Move the arm along it's travel and observe the headlight movement. if its irratic, use a multimeter to check the sensor output is linear and not broken.

If it's a bad reading replace the sensor.

gary

aspire · December 11, 2009

Thanks to you both. Since posting this they've been fine! But I'll probably have to do something fairly soon - winter nights etc. I've printed out the techy stuff to show to whoever I decide to take the car to, I'm not skilled enough to DIY.

Derek

paul_k · December 19, 2009

Yes its the Potentiometer on the rear axle.

Symptoms are:

Headlights moving up and down

Headlights pointing too low

Self levelling light flickering or staying on

My SC has had the potentiometer changed twice now.

Is the only problem I've had on this car in 3 years.

Paul

SC-berks · January 11, 2010

Yes its the Potentiometer on the rear axle.
Symptoms are:

Headlights moving up and down

Headlights pointing too low

Self levelling light flickering or staying on

My SC has had the potentiometer changed twice now.

Is the only problem I've had on this car in 3 years.

Paul

yep, I've got this problem. RE: the potentiometer ( what a name! ) how much does it cost and is that a dealer job? or can my local mechanic do it?

lizzy borden · January 11, 2010

Yes its the Potentiometer on the rear axle.
Symptoms are:

Headlights moving up and down

Headlights pointing too low

Self levelling light flickering or staying on

My SC has had the potentiometer changed twice now.

Is the only problem I've had on this car in 3 years.

Paul

yep, I've got this problem. RE: the potentiometer ( what a name! ) how much does it cost and is that a dealer job? or can my local mechanic do it?

Not something that i've looked at yet, so not sure about a repair. It's a dealer part, but easy to fit yourself if you want to avoid labour costs.

cmarksmith · March 7, 2010

My 2002 SC430 has been maintained by an independent garage rather than the dealer, for a while, but I went back to ask about my self-levelling headlamp problem, and it is not a job they are equipped to deal with.
The warning light on the dash comes on intermittently, and even when it is not on, sometimes the lights seem to be "hunting" up and down for the correct position.

I could return to the Lexus dealer, but my garage recommended a local auto-electrician "as long as they are motorised, rather than pump operated."

Can someone advise if they are motorised or pump-operated? Any other thoughts on the subject also welcome - including any experience of the cost of repair.

Derek

They are on motors.

It's probably the sensor on the back axle.

It's easy to diagnose. jack the car up and remove the sensor but leave it plugged in. Move the arm along it's travel and observe the headlight movement. if its irratic, use a multimeter to check the sensor output is linear and not broken.

If it's a bad reading replace the sensor.

gary

Hi Gary, I have the identical problem. Could you let me know where the sensor is located on the back axle please? Is it easy to spot? Kind regards, Colin

lizzy borden · March 14, 2010

Hi Gary, I have the identical problem. Could you let me know where the sensor is located on the back axle please? Is it easy to spot? Kind regards, Colin

On the passenger side bud. You'll spot it attached to the lower arm.

cmarksmith · June 15, 2010

Hi Gary, I have the identical problem. Could you let me know where the sensor is located on the back axle please? Is it easy to spot? Kind regards, Colin

On the passenger side bud. You'll spot it attached to the lower arm.

Thanks Gary. Found it fine. Regards. Colin

Newbie Lexy · August 5, 2021

Hi, this is a late post (almost 11 years later ) but I now have the same problem, ie an intermittent orange headlamp light on the dashboard. Does anyone recall the part number for this ? Also can anyone recall the cost of dealer fixing it? Complexity of fixing it independently?

Thanks