Abs locking on

[kempes]

For a while now the traction light will start flashing on my dash causing the abs to kick in locking the wheels for a few seconds then releasing them when the service light and ESP light come on together, really stuck with what to do now as I've had it on diagnostic machine twice and changed the brake sensor switch to no avail! Anyone got a solution? In desperate need of one! Cheers

 

[DrR]

Checked the abs rings?

 

[kempes]

no mate,feels like its the back wheels to be fair,dodgy sensor?? are these easy to replace?

 

[DrR]

Check he abs rings, they can crack get dirty etc, trick the car into think the wheels locked.

 

[.Ben.]

^ IME, broken or grease-filled reluctor rings normally result in low-speed firing of the ABS (pulsing through the pedal). They also don't tend to show a fault on the dash.

Sorry I can't help with an alternative suggestion on what the problem might be though, Kempes.

 

[kempes]

cheers lads will have to check these rings out,nothing but trouble this car!

 

[kempes]

got it booked in for tuesday to check the rings,hope it ain't gonna be expensive!!

 

[kempes]

if the rings are cracked are these easy to replace or will i get all the usual crap about needing a new drive shaft etc? wanna do this on the cheap really!

 

[.Ben.]

You can check the rings very easily using a torch! The failed ones are *likely* (95% probability) to be the fronts.

Under the front bumper, look at the inside of the wheel and look for the toothed ring as seen here (not a Clio):

Cracked rings are a pretty straightforward fix for any DIY mechanic. I'd allow a few hours for a newbie.

IIRC:
- Jack car up
- Wheel off
- Hub nut loosen
- Free drive shaft (Careful that the d/s doesn't come out of the gearbox on the passenger side!)
- Remove the 2 ball-joint nuts under the wishbone
- Hub nut off
- Slide shaft out of hub
- Remove old ring (if it's cracked, this'll be easy!)
- Carefully fit new ring (£10 ebay, I seem to recall that OE ones are £25 from Renault for the 172) - Interference fit so need bashing on evenly around the shaft.
- Clean-up and [reverse process]

 

[kempes]

cheers mate,got it booked in at a mates garage on tuesday so hopefully get it sorted