Red Brake Light on Dash

[Josh Tagg]

Bump!
I still have not been able to rectify this and MOT is just a coupe of weeks away.... I plugged the original MC back in and it made no difference. Occasionally I am getting ABS light flicker but I think that may be air or a dodgy sensor. Does anyone happen to know the resistance of a working sensor for an 80series?

Is there a way to activate the ABS remotely so I can bleed it singlehanded or does it not require this level of detail?

Garfieldus sorry I missed your earlier question but I guess it has been answered by those who know. I suppose my original query was what parts of the braking system are connected to this light. I assumed it was just the fluid level indicator but maybe there is also a wire from the ABS possibly.

The abs sensors on mine measured around 720 ohms and the light isn't on. Mines a 1994 12 valve.
Hope this helps

 

[Josh Tagg]

The fronts should read between 900 - 1800 ohms I think.

 

[IRLGW]

ok thanks josh that's a reference point anyway although I am hoping that if I do have a dodgy sensor it will all be relevant to the other three. My only reason for thinking it is a sensor is that I forgot to remove it when trying to pull out the cv joint and it got a few clunks before I realised. now secondary to this, the Milner inner axle seal has failed already ( could be my fault but haven't looked yet) it is also possible that the oil/grease on the abs ring is confusing the system. next step will be to put a resistor across the master cylinder connector and see if that takes it out. otherwise the bulb might have to fall out....

 

[Josh Tagg]

ok thanks josh that's a reference point anyway although I am hoping that if I do have a dodgy sensor it will all be relevant to the other three. My only reason for thinking it is a sensor is that I forgot to remove it when trying to pull out the cv joint and it got a few clunks before I realised. now secondary to this, the Milner inner axle seal has failed already ( could be my fault but haven't looked yet) it is also possible that the oil/grease on the abs ring is confusing the system. next step will be to put a resistor across the master cylinder connector and see if that takes it out. otherwise the bulb might have to fall out....

Haha sometimes them bulbs do just blow..... If you're planning on doing them seals just pull the plug of the abs sensor while you're there and test them see if pulling the cv out caused any damage. I hope this doesn't occur to me-ive got a milners master cylinder in the back waiting to be fitted!

 

[Dave]

Have you checked the float switch is making and breaking?

 

[IRLGW]

No I haven't actually checked the floater but that will go the list. I have checked the nearside front ABS @990 ohms, two rears @770ohms. interestingly the rear nearside wheel bearing was a bit loose and there was movement in the hub so have sorted that and ordered new discs all round as well. I have also been having the abs kick in under light braking like when the front wheel bearing is loose and bull to one side so possibly the rear wobble was a factor. offside front abs check tomorrow and then off to the central mental to recover for a few days...

 

[IRLGW]

ok the light has now gone off! Why -I'm not entirely sure but the only significant thing that I have done is remove the play from the rear wheel bearing. Now that's not to say it might not come back on but there you go- maybe the system is monitoring the feedback from the abs ring...

 

[flint]

I think you’ve probably got the answer. A few years ago, I looked at a car that was having intermittent ABS light troubles. All seemed fine on the OBD reader, but as I was checking around I noticed that the near side front hub unit didn’t look quite seated. It turned out that the hub unit had been replaced and the garage (I use that term loosely) had used a press instead of the special tool needed for a Generation 2 hub, with the consequence that the hub hadn’t clicked home properly and was slowly working its way loose, allowing the ABS ring to flop about. With the unit properly seated, no more ABS probs.

 

[IRLGW]

B******S!! Drove down the road and when I braked at the T junction it came back on. I wonder if disconnecting and reconnecting the senor leads reset it. However that again pushes the chance there may be input from the ABS unit to that light as well as the fluid level.

There is ABS activation and a serious pull to the right so I have just removed the front offside hub to replace the disc and the caliper was a bit stuck to the old one so I think some of the problem might be a sticky caliper- I freggin hope...I have rebuilt the front hubs over the last year and the bearings seem tight enough so it must be something else in this case. The final ABS sensor resistance was 1036ohms so think that's ok. I also found a link via google to this post and it seems that only fluid level or pressure difference can activate the light.

https://www.landcruiserclub.net/community/threads/brake-warning-light-has-come-on.134525/

 

[IRLGW]

Serviced calipers and dropped a piston (longstory). So I decided to do a brake reservoir change to put the Toyota one with switch, onto the Milner master cylinder = light still on.refilled and bled system. Nearside very difficult to bleed?

Drove a few miles and ABS still activating and pulling to the right but RED brake warning light now gone out....

Is the dual system split front/rear or nearside/offside? Does anyone know what the output pressure should be from the MC on each system?

Also does the LSPV really need bleeding if the rear calipers are bleeding ok?

 

[Josh Tagg]

I know most cars should be set up so they split the system diagonally so you still get even braking. In regards to the pressure im not too sure what you'd expect mate.

 

[IRLGW]

ok if thats the case it spoils my theory on the MC causing the problem in which case it must be the abs unit that is causing the restriction. Bloody bleed nipple sheared off the lspv so that one will have to wait also.

 

[Julian T]

On my 80 the front and rear brakes are supplied by one line to the front and one to the rear that supplies both calipers via a T piece at the axles the rear are supplied via the LSV, mine has no ABS.

 

[flint]

Might be worth slipping the boot off the LSPV and checking that the pin is still moving freely.

 

[Josh Tagg]

Did you ever get to the bottom of this irlgw? I've just fitted a Milner master cylinder I bought long before this started, brakes work ok no abs light but that litre red one has come On! Just wondered if you solved the puzzle