Up Owners Club banner

1 - 12 of 12 Posts

·
Registered
Joined
·
16 Posts
Discussion Starter · #1 ·
Good day,

A few days ago after I came back from the car wash my vw up started showing three different warning lights at the same time.
The tire pressure light, ABS and the tracktion control lights.
I did some reading up and found out that most likely one (or more) of the wheel speed sensor(s) could be the fault.

My question is: Is this something common on the up? And should I be worried about something more?

Also can I drive the care like this?

And what does something like this cost?

Is someone has the answer to atleast one of these questions it would be great.

Thank you.
 

·
Registered
Joined
·
984 Posts
No it's not especially common for Ups. This can happen on any car. I expect the sensor or wiring connector has got very wet. Should be easy to sort out.

It's possible that ABS may not work, but you'll still have working old-school brakes. Go easy...
 

·
Registered
Joined
·
28 Posts
HI I had a nightmare on my previous golf with these. But as Freemansteve says let them dry-out first. The perforated discs ( reluctor rings) can get buckled and they are easy to replace. So I replaced the sensor first, no cure. I tried to buy the discs but mine was a late crossover car and I would have had to buy complete new hubs! Anyway the rings were not buckled so I carefully machined the plastic sensors down so they went in the holder further to decrease the gap between sensor and disc. That cured it and was working a couple of years later when I sold the car. If you have an airline you could try blowing round the sensor With an appropriate mask on of course. Basically the Inductive sensor gives a small voltage for each spoke of the disc wheel that passes. The faster the spoke passes the higher the output. so they are basically speed sensors. if one wheel locks and skids on ice and the other turns The BRAIN knows and the ABS comes on. Usually if one wheel is turning slightly faster that the other, The BRAIN predicts you have a flat tyre. Hence the warnings. If nothing else works you could just replace the sensor, it just fits behind the hub with a plug on it costs about £12. Not guaranteed to fix it but a cheap first shot. Meantime just drive as if you don't have ABS but its probably a MOT failure.
 

·
Registered
Joined
·
984 Posts
The sensor output should be same, level-wise, but the frequency of pulses increases, and that pulse rate is counted by the ABS electronics. The sensor is pretty much like a pickup on an electric guitar.

I imagine you can probably measure if there is any sensor output with a DVM set to AC (which should give a RMS voltage), by spinning the wheel. Some DVMs have frequency measurement which should be varying with wheel speed, but the question is whether the sensor is generating enough of a peak voltage to be 'enough' to be seen by the electronics - someone who's looked into it may know what the voltage level should be of the pulses; I only know the theory!
 

·
Registered
Joined
·
16 Posts
Discussion Starter · #5 ·
The sensor output should be same, level-wise, but the frequency of pulses increases, and that pulse rate is counted by the ABS electronics. The sensor is pretty much like a pickup on an electric guitar.

I imagine you can probably measure if there is any sensor output with a DVM set to AC (which should give a RMS voltage), by spinning the wheel. Some DVMs have frequency measurement which should be varying with wheel speed, but the question is whether the sensor is generating enough of a peak voltage to be 'enough' to be seen by the electronics - someone who's looked into it may know what the voltage level should be of the pulses; I only know the theory!
Thank you very much for the insight. Tomorrow I have a appointment at the garage to get the fault read out, so they can determine what the problem is actually. I will post the results after.
 

·
Registered
Joined
·
16 Posts
Discussion Starter · #6 ·
HI I had a nightmare on my previous golf with these. But as Freemansteve says let them dry-out first. The perforated discs ( reluctor rings) can get buckled and they are easy to replace. So I replaced the sensor first, no cure. I tried to buy the discs but mine was a late crossover car and I would have had to buy complete new hubs! Anyway the rings were not buckled so I carefully machined the plastic sensors down so they went in the holder further to decrease the gap between sensor and disc. That cured it and was working a couple of years later when I sold the car. If you have an airline you could try blowing round the sensor With an appropriate mask on of course. Basically the Inductive sensor gives a small voltage for each spoke of the disc wheel that passes. The faster the spoke passes the higher the output. so they are basically speed sensors. if one wheel locks and skids on ice and the other turns The BRAIN knows and the ABS comes on. Usually if one wheel is turning slightly faster that the other, The BRAIN predicts you have a flat tyre. Hence the warnings. If nothing else works you could just replace the sensor, it just fits behind the hub with a plug on it costs about £12. Not guaranteed to fix it but a cheap first shot. Meantime just drive as if you don't have ABS but its probably a MOT failure.
Ah ok. Thank you. So what your saying is that it shouldn't be a difficult fix. 12 pounds also seems pretty reasonable.
 

·
Registered
Joined
·
28 Posts
Ah ok. Thank you. So what your saying is that it shouldn't be a difficult fix. 12 pounds also seems pretty reasonable.
Well £12 is the cost of the sensor if you buy it from GSF or similar. I just found out our local VW dealer charges £126 per hour. for repairs!
 

·
Registered
Joined
·
295 Posts
If a car has been stood for a long time or the battery has drained very low the steering angle sensor may need resetting. To do this just wind the steering lock to lock a couple of times. Then turn off and re start.
Worth a try 👍👍
 

·
Registered
Joined
·
984 Posts
Also a battery disconnect/reconnect should cause various system resets, which may help, but something important like ABS may stay still "latched" as a system fault in terms of dash lights - it will definitely stay in the OBD log until cleared.
 

·
Registered
Joined
·
295 Posts
Also a battery disconnect/reconnect should cause various system resets, which may help, but something important like ABS may stay still "latched" as a system fault in terms of dash lights - it will definitely stay in the OBD log until cleared.
Not all things get registered in the OBG log as you call it but your words raise an interesting point.
When VW ECUs register a fault the ECU can and more often than not “Snapshot” the cars odometer....
So say it registers a C02 fault for instance and it snapshots the odometer when the codes are interrogated by a suitable diagnostics tool the odometer reading can be viewed.

Before buying my Up GTI I was going to buy a Polo GTI. In fact I put a deposit on it. The cars odometer read 32,000 miles.
I was registered on a Facebook page dedicated to the Polo GTI. I put a picture of the car up on that page and within hours I was told by its previous owner that he had sold the car with 43,000 miles registered on it’s odometer..
Cut a long story short the car was taken into Cheltenham VW who connected it to their kit and a minor fault was stored on the ECU with the mileage snapshot at 40.000 miles.
In other words the car had been clocked. So I got my deposit back.

These ECUs are clever things. Clever enough to catch out some who think they can play around and alter things and not get caught...

I use a fairly sophisticated Diagnostic box that is capable of interrogating every system on a car. Gearbox ECUs ....ABS .. Airbags all the lot of it but it’s not VW specialised so would not have pulled up the snapshot feature.
 

·
Registered
Joined
·
16 Posts
Discussion Starter · #11 ·
Just came back from the garage. Apparently a little bit of water got into the connection point between the sensor and cable causing it to short on and off. I switched the sensor anyways. They charged me 70 euros for everything. Now it's just to wait and see if the problem persists, but I doubt it. I saw it with my own eyes.
Would have saved a couple bucks if I just undid it myself and dried the sensor.....but I guess it's OK.
6341
6342
 

·
Registered
Joined
·
984 Posts
Good job...
And as per my first post!
€70 is not too bad for parts and labour - better than being in the cold messing with it yourself!
 
1 - 12 of 12 Posts
Top