Brake Wear Sensors Cry Wolf + 2 Questions

[AdeV]

My LS400 brake wear sensor came on the other week (whilst I was towing a car on a trailer..... always good for the nerves, that). So today, I finally got around to checking all the pads. Rears were well down (replaced), but the fronts still have over 1/2 the pad thickness remaining, yet both sensor wires are down on the disc!!

:tsktsk:

I reckon I've got at least another 3-4000 miles in them yet. But obviously I'll have to buy a new set of sensor wires, as by the time I'm ready to replace the pads, I'll have worn my way all the way through the wires.... that'll be another £60-odd then. Of course, I would save myself the cost of the wires & just change the pads (or take the wires off), but one of them's already worn all the way through the lead contact & is eating the wires, so I'd need new ones even now.

Grumble.

Oh, a couple of questions:

1) If I have to do an emergency stop (or very hard braking), the warning triangle on the dash lights up. It goes out again as soon as I've stopped braking. Had that twice on the motorway recently (usually when some eejit pulls out from behind a lorry, having failed to notice me "making progress". Any idea why this should be? Brake fluid level is fine, maybe it's getting a bit old & wants replacing?

2) I've obviously got a dicky stop-light, as sometimes the warning light comes on & stays on. Usually, opening & closing the boot is enough to cure this for a period of time (or, firmly tapping the light cluster with the palm of my hand). The trouble is, I've never managed to diagnose it... Is it likely to be a loose bulb, or a bad joint somewhere?

[steve2006]

Hi,

Not sure about the Triangle warning light as I cannot locate the symbol but the other problem you have is the old chestnut problem of the wiring loom breaking in the boot where it passes over the left hand boot hinge ( looking from the rear).

If you do a search there are loads of threads on here for the same problem.

[ROYT]

As you are aware of the pad condition, why not just join the wires [to put out the warning light] and replace them when you do the front pads?

[AdeV]

Hi,

Not sure about the Triangle warning light as I cannot locate the symbol but the other problem you have is the old chestnut problem of the wiring loom breaking in the boot where it passes over the left hand boot hinge ( looking from the rear).

If you do a search there are loads of threads on here for the same problem.

Apologies - it's not a triangle, it's a "brake drum" symbol (circle with stylised shoes outside of it), and an exclamation point in the centre.

The only thing the Lexus manual has to say about it is (paraphrased): "Serious braking system problem - get back to Lexus ASAP before you crash through someone's garden wall!"

As I say - most of the time it's just a flakey brake light (I will check the loom out, sounds promising); but it also lights briefly if I have to brake REALLY hard...

[AdeV]

As you are aware of the pad condition, why not just join the wires [to put out the warning light] and replace them when you do the front pads?

Would joining the wires work? I'd guessed that simply disconnecting them would be the best option (as the disc is currently completing the circuit between the two wires).

Anyway, I'll have a play with the various options next time the car is near the ramp...

Cheers,

Ade.

[leonc17]

As you are aware of the pad condition, why not just join the wires [to put out the warning light] and replace them when you do the front pads?

Would joining the wires work? I'd guessed that simply disconnecting them would be the best option (as the disc is currently completing the circuit between the two wires).

Anyway, I'll have a play with the various options next time the car is near the ramp...

Cheers,

Ade.

tride this on omega did not work after fitting new brakes broke plug so twisted wires light still on any ideas

[ROYT]

On LS 400 the pad warning wires are worn through to put on the 'pad warning light'

If all warning wires are unbroken i.e not open circuit the light will stay off.

Joining a broken wire or wires, more than one may be faulty, will put out the light!

[floggit]

Hi,

Not sure about the Triangle warning light as I cannot locate the symbol but the other problem you have is the old chestnut problem of the wiring loom breaking in the boot where it passes over the left hand boot hinge ( looking from the rear).

If you do a search there are loads of threads on here for the same problem.

Apologies - it's not a triangle, it's a "brake drum" symbol (circle with stylised shoes outside of it), and an exclamation point in the centre.

The only thing the Lexus manual has to say about it is (paraphrased): "Serious braking system problem - get back to Lexus ASAP before you crash through someone's garden wall!"

As I say - most of the time it's just a flakey brake light (I will check the loom out, sounds promising); but it also lights briefly if I have to brake REALLY hard...

Hi adeV ref the brake drum warning light coming on under heavy braking . Ive had this a few times to and have had it checked out, Have been advised fluid level ok but under heavy braking the level moves away (i.e, forward ) of the sensor.

As soon as u stop the level settles and the light goes out. Nothing to worry about, just check all fluid levels regulalry to be on the safe side .

steve.

[AdeV]

Hi adeV ref the brake drum warning light coming on under heavy braking . Ive had this a few times to and have had it checked out, Have been advised fluid level ok but under heavy braking the level moves away (i.e, forward ) of the sensor.

As soon as u stop the level settles and the light goes out. Nothing to worry about, just check all fluid levels regulalry to be on the safe side .

steve.

Thanks Steve - I did wonder if it was something like that... the levels are fine, but I can see how an emergency stop would cause that.

When I replace the front pads, I'll probably do the fluid at the same time, as it'll be at least a year old then.

Cheers!

Ade.

[ffcary1]

My LS400 brake wear sensor came on the other week (whilst I was towing a car on a trailer..... always good for the nerves, that). So today, I finally got around to checking all the pads. Rears were well down (replaced), but the fronts still have over 1/2 the pad thickness remaining, yet both sensor wires are down on the disc!!

:tsktsk:

I reckon I've got at least another 3-4000 miles in them yet. But obviously I'll have to buy a new set of sensor wires, as by the time I'm ready to replace the pads, I'll have worn my way all the way through the wires.... that'll be another £60-odd then. Of course, I would save myself the cost of the wires & just change the pads (or take the wires off), but one of them's already worn all the way through the lead contact & is eating the wires, so I'd need new ones even now.

Grumble.

Oh, a couple of questions:

1) If I have to do an emergency stop (or very hard braking), the warning triangle on the dash lights up. It goes out again as soon as I've stopped braking. Had that twice on the motorway recently (usually when some eejit pulls out from behind a lorry, having failed to notice me "making progress". Any idea why this should be? Brake fluid level is fine, maybe it's getting a bit old & wants replacing?

2) I've obviously got a dicky stop-light, as sometimes the warning light comes on & stays on. Usually, opening & closing the boot is enough to cure this for a period of time (or, firmly tapping the light cluster with the palm of my hand). The trouble is, I've never managed to diagnose it... Is it likely to be a loose bulb, or a bad joint somewhere?

Just replced a pad sensor on my 93 ls400 and it cost £52.00. what a rip off, but being silly old me it is something that just has to be done., ie if its broke i gotta fix it. I have not had it long and i am still fixing the bodges that the last owner did. I wil get it sorted though. just you watch and toyota will all the richer foe it as well.