But I'm stumped with this 1 so I may have to admit defeat and cough,
![Cry :cry](./images/smilies/icon2_cry.gif)
Renault megane est, ABD and ESR and ASR warnings lit up.
If anyone can sense check this for me I'd appreciate it
All wheels removed and sensors cleaned and wiring inspected, all looks well.
Reluctor? rings not visible, part of the drive shaft at the front and the wheel bearing at the rear.
Resistance of each sensor checked, all 12 ohms, there must be a diode in there as they are polarity sensitive.
Car lifted and an ac voltage check on all sensors whilst spinning wheels, no reading on either an analogue or digital meter. Checked either polarity.
After removing half the under bonnet and bulkhead arrangement, including the wipers, I finally gained access to the ABS ecu, it's part of the ABS hydraulic unit. Removed wiring connector, cleaned, and refitted.
OBD11 doesn't interrogate this ABS ecu, needs a more specialised scanner methinks.
As I understand it the ABS ecu checks the resistance of each sensor whilst stationary, in the 1st 2 seconds, then the output of them when on the move.
The light comes on whilst stationary.
Anyway, no better, car can be driven but brakes revert to non ABS operation. MOT failure of course.
So unless anyone has any ideas or something I may have missed it's a trip to the rip off specialists.