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Mamasbigtruck

Member
Since I've had my P38 it has reported low brake fluid and the little red light is on

I bridged the wires on the sensor but no change
No faults reported in Nanocom
ABS pump switch swapped, no change
The low fluid is only reported when the ABS pump stops running, and I have noticed that the pump kicks in on every 2nd press of the pedal, I take it this means an accumulator is ideally needed,

Could a low accumulator cause this?

Brakes and ABS do work properly
 
That is because the fluid is low after pump has pressurised sphere. Switch ignition on and wait until pump stops only then fill fluid to max point. Fluid will be well above max when car has been stood a while. Reference every second application. Change accumulator it is low on nitrogen.
 
When system was unpressurised i filled it to the brim, when pump has stopped it is still well above max mark.

I'll order an accumulator

The fluid sensor is a weird thing, it slides out of the reservoir and is it's own sealed dry chamber and has a sort of glass encapsulated reed switch connecting the two terminals, not too sure how it works
 
Mamasbigtruck said:
When system was unpressurised i filled it to the brim, when pump has stopped it is still well above max mark.

I'll order an accumulator

The fluid sensor is a weird thing, it slides out of the reservoir and is it's own sealed dry chamber and has a sort of glass encapsulated reed switch connecting the two terminals, not too sure how it works
Click to expand...

Its like a float in side the fluid drops so does the float.
 
That's what I thought, but the sensor does not actually go inside the tank, it slides out sideways from the tank and is just a couple of wires and this glass encased reed switch. the hole it sits in is a dead end with no access to fluid. there is a vague picture of the sensor on Rave page 834

The must be a float in there but is can't be seen or touched even with the filler filter take out as it sits in the back portion of the tank. Quite how it operates the switch though, does not respond to a magnet.

Bridging the wires should stop the warning but it does not. Driving me mad.......more mad

Could this be a MOT item?
Where the hell are the circuit diagrams in Rave?
 
Mamasbigtruck said:
That's what I thought, but the sensor does not actually go inside the tank, it slides out sideways from the tank and is just a couple of wires and this glass encased reed switch. the hole it sits in is a dead end with no access to fluid. there is a vague picture of the sensor on Rave page 834

The must be a float in there but is can't be seen or touched even with the filler filter take out as it sits in the back portion of the tank. Quite how it operates the switch though, does not respond to a magnet.

Bridging the wires should stop the warning but it does not. Driving me mad.......more mad

Could this be a MOT item?
Where the hell are the circuit diagrams in Rave?
Click to expand...
Must be a broken wire or your handbrake switch is buggerd .
 
I'll check handbrake switch but the display definitely states brake fluid low.

Time to trace wires back, I know where it enters the BECM maybe I can stop the warning here instead.
 
Mamasbigtruck said:
I'll check handbrake switch but the display definitely states brake fluid low.

Time to trace wires back, I know where it enters the BECM maybe I can stop the warning here instead.
Click to expand...

What the message centre? or the light you have a red abs light and a round brake light with an exclamation mark in the middle some times fluid and handbrake are on same light not too sure about the rr never had to look into it as yet
 
Ignition on, Yellow ABS lamp on and exclamation warning lamp, after ABS pump stops message centre says low fluid and exclamation lamp stays on. Abs lamp goes off when driven as it should.

Does the message centre not say handbrake on or something like that?
 
Mamasbigtruck said:
Ignition on, Yellow ABS lamp on and exclamation warning lamp, after ABS pump stops message centre says low fluid and exclamation lamp stays on. Abs lamp goes off when driven as it should.

Does the message centre not say handbrake on or something like that?
Click to expand...

Ok broken wire look at the subsections is rave you should find it persevere.
 
Thanks, I have to track down wiring diagram first. but will have a quick look tomorrow, doing balljoints is my priority if the weather is not bad.
 
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