Handbrake light on when accelerating

[DaveDreads]

When accelerating the handbrake light is permanently on, it goes away off throttle or braking, when maintaining a constant speed with the throttle it flickers, i've checked the brake fluid reservoir and it's full, usually when you fluid is low the STOP and brake light comes on when cornering, also when going up hill on throttle it's on constantly, but off throttle up hill or stopped with the foot brake it isn't on which is odd, if it was to do with the fluid it should be on when pointing up the same hill throttle or not.

The only thing I can think that's changed is the handbrake cable was recently tightened when new rear pads were fitted, so maybe the sensor can't tell when the handbrakes on or off, but that wouldn't explain it flickering or only really being permanently on when accelerating, any ideas?

 

[Tez clio]

When accelerating the handbrake light is permanently on, it goes away off throttle or braking, when maintaining a constant speed with the throttle it flickers, i've checked the brake fluid reservoir and it's full, usually when you fluid is low the STOP and brake light comes on when cornering, also when going up hill on throttle it's on constantly, but off throttle up hill or stopped with the foot brake it isn't on which is odd, if it was to do with the fluid it should be on when pointing up the same hill throttle or not.

The only thing I can think that's changed is the handbrake cable was recently tightened when new rear pads were fitted, so maybe the sensor can't tell when the handbrakes on or off, but that wouldn't explain it flickering or only really being permanently on when accelerating, any ideas?

I was gonna say check the reservoir as iv read this today. I also read to unplug the resovoir sensor and see if it still flickers this will check whether that's faulty.

 

[Bluebeard]

Low brake fluid would be my bet.,

 

[DaveDreads]

Fluid is full as far as I can tell, although the gap between max and min is very small, looks to be about a 20mm difference.

Also why wouldn't it come on when pointing up or downhill but only on throttle, surely if it was low fluid it should do it on all inclines, not just on throttle?

 

[celicaturbolly]

It may just be dirty so causing a bad reading on the level sensor. You can get one of those turkey baster things to get some of the old fluid out, then replace with new?

 

[DaveDreads]

That sounds like a plan, it's been in there a few years and it was on my to do list before CSF track day, I just don't get how it was fine when the pads were near enough grinding and the piston was fully out, but now the pads are new and the piston is wound in it's gone haywire.

 

[Dr HMS Derv Destroyer]

aslong as your still getting a good pedal no spongy feeling or loosing fluids from any of four corners then it's not a major issue. Level sensor on the bottle cap possibly playing up , or the fluids that shitty now it's having hard time reading levels

Wiring ok to the lid or has it been snatched / melted on anything

 

[DaveDreads]

The sensor on top of the bottle is all sh*tted up with gunk, I think it's more than likely the fluids that old it's full of crap and needs flushing, tbh I might just Turkey Baste it out and stick some fresh in, i've no idea what grade of fluid's in there, will mixing Dot4 and Dot5.1 make any difference?

 

[Dr HMS Derv Destroyer]

Only put dot 4 with dot 4!!
I'd add it to yoUr list for some better brake fluid ( super blue ect ) for a full flush ect before the track day mate.

Ideally you need brake cleaner to clean the bottle top and sensor

 

[Dr HMS Derv Destroyer]

Have you checked The micro switch on the handbrake isn't all shitted up as it was like a fluff pit under that trim PMSL!

 

[DaveDreads]

No and I resent the implication that everything in my car is sh*tted up with dog hair! *goes off to clear all the dog hair out the micro switch*

 

[Dr HMS Derv Destroyer]

Any good?

 

[DaveDreads]

I haven't driven it yet, i'll let you know tomorrow.

 

[McGherkin]

Have you checked The micro switch on the handbrake isn't all shitted up as it was like a fluff pit under that trim PMSL!

His engine bay's probably cleaner than the interior. It's a good chance.