ABS Warning light

[garibaldy]

Oh bugger, the ABS amber warning light came on (permanently) on my mk1 Fabia 1.2HTP this morning so I've been doing a lot of research about possible causes. I've seen several posts about cracked 40A strip fuses for the ABS although the fuses look fine to me (see below). I've swapped over the 40A fuses which are 3rd and 4th from the left on top of the battery looking at the front of the car but it hasn't made any difference after a short drive. I think one of these is the ABS fuse on my model?

 

I haven't got a reader :-( but i suppose that's the next logical thing to do. Anything else I can look at without a reader? Brake lights are working.

[KenONeill]

Well, these are usually a failed wheel sensor or break in the associated wiring, so you actually need VCDS or similar for diagnosis. VCDS Lite and a good OBD2 to USB cable are cheaper than a garage charge for reading codes.

[garibaldy]

i was chasing my tail replacing wheel sensors on a E39 BMW i used to have which was a red herring. I was wondering if there are other areas to look out for on the Fabia which may throw up an ABS warning light.

[Breezy_Pete]

Yep, fuse 4 on your car. 

Any wheel bearings been replaced lately?

Happy to scan it with VCDS for you if you can get to me in Abingdon area, but there's almost certainly someone closer to you. Or kit yourself out as Ken suggests.

[garibaldy]

Thought so, thanks for the confirmation. I've already ordered a new 40A strip fuse just in case both are damaged (i dont recall ever hearing the radiator fan come on whic i think is fuse 4).

 

No wheel bearings have been replaced AFAIK.

 

Thanks very much for the offer to scan the car. I'm about 45 mins from you,  but I will let you know if the replacement fuse doesn't fix it!

[Breezy_Pete]

Fuse 3 is rad fans, but only their high speed action; low speed is No.8, a blade fuse in the covered bit to the right of the strip fuses, 30A. Check that one is OK. Putting A/C on will normally result in fans coming on after a while, as an easy test of function.

[fabdavrav]

I'd do voltage/continuity checks across those fuse blades as hair line cracks can be difficult to see with the naked eye..

 

Also a main battery on it's way out can cause various ABS lights

[garibaldy]

Thanks for the advice. The battery was replaced in July last year but I will test it out too.

[garibaldy]

Hoping to get the replacement fuse tomorrow as the local VW dealer just informed me they'd made a mistake :-(

[garibaldy]

VCDS lite appears to be free looking at Ross-Tech. Am I looking at the right tool? Do you have any recommendations for a reliable cable?

[garibaldy]

Replacement fuse hasn't fixed the problem so i'm going to download VCDS Lite and buy an OBD2 to USB cable. Can anybody confirm that this is the correct cable for my Fabia :-

 

http://www.gendan.co.uk/product_VAGUSB_16.html#product_information

 

Cheers.

[Breezy_Pete]

Yep. That's what I have.

[garibaldy]

Thanks Wino, cable ordered.

 

I've just been out in the car again and initially the ABS warning light wasn't lit :-) . However, when I got back to the car after shopping the ABS warning lit up again.

[Breezy_Pete]

I suspect you'll see a fault reported with one of the wheel sensors giving intermittent info to the ABS ECU, once you've got your laptop and cable chatting with the ABS module.

Have the wheels off one at a time for a look at the wiring coming off each of the sensor plugs if its a nice day tomorrow; just as likely to be a 'waggled too much' wire fault as a dodgy sensor, I should think.  May not be anything visible though.  Good opportunity to eyeball the brakes/inner sidewalls of tyres and other usually hard to see bits and bobs though.  

 

[garibaldy]

I had the OSF tyre replaced a couple of weeks ago. I wonder if the sensor/cable cable got knocked - seems very unlikely but you never know. I will start there and work my way around.

Edited 20 May, 2017 by garibaldy

[davidwhite]

1 hour ago, garibaldy said:

I had the OSF tyre replaced a couple of weeks ago. I wonder if the sensor/cable cable got knocked - seems very unlikely but you never know. I will start there and work my way around.

 

That sounds like a logical plan, hope it's something as simple as that, had issues with the abs on a old car once right pita I think that other than the bulb lighting up there were no other obvious issues seem to remember removing the bulb before px' ing the car ( hangs head in shame !! )

[garibaldy]

Took the OSF wheel off on Sunday but there was no obvious sign of damage to the sensor cable. I didn't have time (actually sunlight) to check the other wheels so will now wait until my OBD2-to-USB cable arrives and see what the diagnostics shows.

 

BTW - How do you unclip the sensor cable from the sensor? It wouldn't budge, even trying to release the "clip" using a flathead screwdriver. I didn't try too hard in case i damaged the connector.

Edited 23 May, 2017 by garibaldy

[sepulchrave]

You have to push on the plug while releasing the clip with the screwdriver, then you should be able to wiggle it off, they're a very tight fit but they do come off.

[garibaldy]

ta very much.

[sepulchrave]

When you put it back on give it a quick blast of WD40, helps it snap back into place, helps keep the water out and makes it much easier to take it off again in the future.

[garibaldy]

My cable arrived yesterday and I've got this fault code :-

1 Fault Found:
00287 -  ABS Wheel Speed Sensor; Rear Right (G44)

        012 -  Electrical Fault in Circuit

Does 'Rear Right' mean OSR?

 

[Breezy_Pete]

Yep.

[Breezy_Pete]

If you want to check the wiring, before spending on a new sensor, as far as I can see, pin 1 of the 2-pin connector that plugs into the sensor should go to pin 19 of the connector at the ABS module, and pin 2 at the wheel should go to pin 31 at the module.

[garibaldy]

When I took the wheel off I noticed that the ABS sensor cable wasn't clipped into the clip further up inside the wheel arch, and i doubt it popped out by itself looking at the design. Not sure what to make of that, but I unplugged the cable from the sensor, did a visual check and it appeared in good condition. Unsurprisingly the ABS light is still on after plugging in the cable and clearing the codes.

 

I've got a multi-meter but i'm no sparky so how do i check the wiring?

Also how much should i be looking to pay for a replacement sensor? Today a pagid sensor is £36 from ECP, a 'standard' sensor is £35 from GSF (both with codes), and I cannot get through to the local VW dealer.

 

Edited 25 May, 2017 by garibaldy

[garibaldy]

Picking myself up off the floor after being told that the sensor from the local VW place costs £81!

Going to have to be ECP or GSF, but i'd rather rule out the cable first.

Edited 25 May, 2017 by garibaldy