What is this switch/sensor

[Reliable]

Just curious,

Does anyone know what this switch or sensor on the rear axle is for? (in red)

Cheers,

[flipsta24]

looks light your headlight adjustment, it adjusts your headlight beam levels, so when there is weight in the rear your headlights will aim down instead of it aiming up

[SuperDave]

Your location says non-au. I haven't seen that on the Sportivos here, nor have I seen those rear brake calipers on a sportivo (assuming I have orientated myself correctly). Euro corolla? Can't help with what it is though.

[Kenshin X]

it would be NZ and that corolla is an import from japan dave.

[Reliable]

looks light your headlight adjustment, it adjusts your headlight beam levels, so when there is weight in the rear your headlights will aim down instead of it aiming up

Now that would be cool, but I dont see how that would work?

Sorry thats just a picture off the internet, but my corolla has the exact same thing.

Kenshin X is right I have a JDM corolla in NZ

[daniboy]

some cars also have a similar sensor for brake bias for the abs to know how much weight is in the rear, and also some vehicles have a ride sensor similar for pushbutton suspension(ie sport or comfort) a lot of older mazdas had this....

[Reliable]

I wonder if I should adjust this then. As the car has been lowered.

Guess I would have to confirm for sure.

Thanks for all your responses

[123R-Prozak]

No

Pfft self adjust bro

If u lowered the front by an inch and the rear by an inch, do u really think it matters? No

[Reliable]

ABS and brake distribution is happening at the limit of traction so yes I think it needs to be a finly tuned system,

What if the car though there was more weight in the back and applied the rear breaks harder and caused a spin mid corner? Infact I think the back end of these cars lets go pretty easy for a FWD.

what does everyone else think?

[trentmeyer23]

That looks a lot like a Load Sensing Valve, they are commonly used in utes and light to heavy trucks to increase braking to the rear wheels when there is additional load in the rear. However, when there is no load, the braking force is not required to be as strong so the valve reduces the braking pressure to the rears and prevent spinning. Due to the car being lowered and the axle being closer to the chassis, the valve thinks there is a greater load and would be applying more pressure.

I would suggest you have it professionally adjusted as they are often very sensitive and if you mess it up it could have serious consequences.

[123R-Prozak]

A brake proportioning valve on a corolla? Sounds like bs to me IMO

[Reliable]

some cars also have a similar sensor for brake bias for the abs to know how much weight is in the rear, and also some vehicles have a ride sensor similar for pushbutton suspension(ie sport or comfort) a lot of older mazdas had this....

Thanks Dan for the helpful comment

ABS and brake distribution is happening at the limit of traction so yes I think it needs to be a finly tuned system,

What if the car though there was more weight in the back and applied the rear breaks harder and caused a spin mid corner? Infact I think the back end of these cars lets go pretty easy for a FWD.

what does everyone else think?

That looks a lot like a Load Sensing Valve, they are commonly used in utes and light to heavy trucks to increase braking to the rear wheels when there is additional load in the rear. However, when there is no load, the braking force is not required to be as strong so the valve reduces the braking pressure to the rears and prevent spinning. Due to the car being lowered and the axle being closer to the chassis, the valve thinks there is a greater load and would be applying more pressure.

I would suggest you have it professionally adjusted as they are often very sensitive and if you mess it up it could have serious consequences.

Sometime it feels like the car breaks too hard on the rear, I can think of two instances where ive been fooling around and touched the breaks mid turn and had the back let go been fine controling it tho, just makes me wonder.

This makes me think even lowering springs with a difrent spring rate would also throw out the calibration hmmmm

[trentmeyer23]

Well after some research it appears to be a height control sensor.

http://www.toyodiy.com/parts/p_J_2005_TOYOTA_COROLLA_ZZE123G-AWFQF_8401.15.html

[Reliable]

Well after some research it appears to be a height control sensor.

http://www.toyodiy.c...QF_8401.15.html

Thank you so much, such a good resource

so it is a:

89407 SENSOR SUB-ASSY, HEIGHT CONTROL, REAR RH

So I guess now it could be for two possible things:

- headlight leveling

or

- Brake Bias / electronic brake force distribution (if so it may be very important to correct it the nearly 2" the car has been lowered in the rear)

What do you guys think?

cheers for all the great work and help so far.

[trentmeyer23]

Did any of the higher spec JDM versions come with ride height levelling?

[123R-Prozak]

Highly doubtfull this controls abs..

[Reliable]

Did any of the higher spec JDM versions come with ride height levelling?

Not that I can find, the mystery goes on....