ABS light wont work

Retrogamer

Stooby2 wrote: »

That's only partly correct - most modern ABS systems need the car to be driven a few metres so the ECU detects a signal from each wheel sensor - and then turns the light off.

Hence the part "usually comes on for a few seconds"
Rarely will be on until car is moved.

I haven't found any modern cars personally that need to be moved for it to go out, but i remember a lot of Landrovers were like that.

mattyprice4004

Stooby2 wrote: »

That's only partly correct - most modern ABS systems need the car to be driven a few metres so the ECU detects a signal from each wheel sensor - and then turns the light off.

Nope, that's wrong.
Pretty much all modern systems do a hydraulic check on starting - then check for continuity to the sensors. If the sensors and hydraulic tests pass, the light goes off (normally 2-4 seconds).

If when the vehicle moves off an implausible signal is received, it'll put the light back on.

If your car has the light on until you move off, something isn't working correctly.

Stooby2

Well it's what I was told in training although trying to think back it may have been "some" rather than all. Both my Discoveries do it (as Retrogamer says it may be a LR thing) and they are 15 years apart in age. The idea is that whilst a continuity check confirms the connection to the sensors, it doesn't confirm whether they are actually where they should be and not hanging by the wire.