just recently my anti lock light came on and now my brakes are playing up. i started the engine and theres a noise in the boot (well it sounds like its coming from the boot) so i start to pull out this drive and the brakes go soft and i hear that noise again, then i take my foot off the brake and it goes back to normal again until i put my foot on the brake again. its ok when im driving down the road and i use the brakes. (the noise sounds like an arial going up)

 

please help someone

 

cheers

Nick

The ABS actuator thingy is in the boot, so makes sense.

brakes go soft ...sound's like air in the brake line's ....

 

...

cheers mate. well it sounds like thats playing up. does anyone know whats causing this to happen or has any ideas?

 

cheers

Nick

something must be causing air to go into the brake lines and to make the anti lock light to come on.

 

Nick

have you been messing with the brakes? There is a bleed point on the ABS unit itself - which I didn't realise until I RTFM!! Can't remember the bleed order now, but worth bleeding them first before loking for other problems...

no i hav'nt been touching the brakes, i first thought it was something to do with the wet weather iv been driving in.

 

Nick

has anyone else got any ideas what i should do, im scared of driving it incase the brakes stop working?

 

cheers

Nick

has anyone else got any ideas what i should do, im scared of driving it incase the brakes stop working?

 

cheers

Nick

HAVE YOU CHECKED THE FLUID LEVEL?

first port of call would be to get the brakes bleed properly and go from there

300zx Service manual - ABS System

HAVE YOU CHECKED THE FLUID LEVEL?

 

yep i always keep that topped up

 

Nick

first port of call would be to get the brakes bleed properly and go from there

 

i will have to do that this weekend!

 

cheers

Nick

If you havnt lost any fluid, and you havnt been playing with the brakes, I would have thought the ABS ECU is playing up. Has someone local got one you could swap with to test??

yep i always keep that topped up

 

Nick

 

 

Fluid level should only go down with Pad wear and not require topping up... ( if you top it up it will only overflow when new pads fitted )

Have you any visible signs of a leak under the car ?

Sounds like the ABS ECU is working when it shouldn't, the pedal will go soft when the unit is modulating. First thing is check the fluid level and for any leaks. Next thing is check the associated electrics. This means the main connector into the ECU, all four Wheel Speed Sensors and their plugs etc. Then start swapping bits with someone, not forgetting the wheel speed sensors, I think you might find one of those is the cause (probably won't now I've said that!).

Big difference between fluid level and air in the system! Get the system flushed and bled....of you have the time and money, get the caliper rebuild kit as well!

 

I had a problem similar to that with a Senator I used to have. Pedal would travel almost to the floor and the ABS would suddenly cut in and I'd have no braking. ABS modulator was shafted I think.

 

I threw the car away in the end. :rofl: