Brake Pressure Sensor

[Nharris89]

Hi All,

I have a permanent traction control light and orange handbrake light on the dash (no abs light though) I checked with INPA and it flags up that the brakes are imbalanced and a pressure sensor has failed. Does anyone know if that would be the cause of the lights?

Many thanks!

 

[filipov]

Before changing any parts try unplugging and plugging again the connector of the DSC module under the hood. This solved the problem for me, as I was getting these errors occasionally. Turned out some cable was not doing a good connection.

 

[mjennings23]

Same as the above, but also the brake pressure sensors (the 2 sensors on the bottom of the master cylinder). I'd also suggest you spray some electrical contact cleaner on both parts.

 

[Nharris89]

Hey guys and girls,

So my traction control light is permanently on at the moment, when I diagnose the fault it tells me there's a defect with a pressure sensor on the braking system. I'm going to replace the sensor out BUT would I need to code the new sensor to my car?! It's a 2004 2.2 SE e85. Hoping I can just swap it straight out job done, but is it as easy as that?!

Any input would be hugely appreciated!

 

[Lance]

I changed a pressure sensor on my 2003 2.5 late last year. Swapped it out, no more light since.

IIRC, the light disappeared after a short drive after fitting the new part.

One out, new one in, that's all I did.

 

[GuidoK]

Hoping I can just swap it straight out job done, but is it as easy as that?!

You know which one you have to replace?
Each brake circuit has its own sensor.

 

[Nharris89]

Thanks both! So I've had a look under the hood at those parts (I assume the unit under the master cylinder is the DSC module) however being a complete novice, I can't get the connectors off of any of the three components to give them a good clean! Is there something im missing?! How do the connectors come off? Thanks all!

 

[Nharris89]

I was going to replace them both just to be safe. I can't seem to get the connectors off the back of the sensors though either! What's the trick?!

 

[Nharris89]

Also, if anyone knows where I can get them that would be great! Euro parts don't seem to stock them!

 

[MJJamieson]

I got mine used with warranty off Ebay for £10. one out one in quick and you won't loose any fluid.

 

[Lance]

I got mine used with warranty off Ebay for £10. one out one in quick and you won't loose any fluid.

I also got a used one from eBay. I changed the easiest one first and that did the trick, had it not I would have swapped the one I took out with the other one. As above, be prepared and be quick to ensure minimal fluid loss.

To dark to look now, but I don't recall any difficulty in removing the connector, there be either a push down or lift up tab to release it. I can look in the morning.

 

[Nharris89]

Update, don't try looking at sensors in the dark, not easy to work out! Got the connectors off this morning, sprayed them all with some contact cleaner and reconnected, turned car back on and the light has gone off. Scanned with INPA and cleared the code memory (5e20 and 5e21 pressure sensors 1 and 2 electrical defect) which had faults on both pressure sensors. Rescanned and no errors. Drove for about five miles and the lights come back on. Unfortunately the scan shows both sensors are bad so I've ordered two and will get those swapped out next week and hope that's the end of it! Thanks everyone, this forums so helpful!!

 

[PeterZed]

I had the same fault it would come up on an intermittent basis, did all the cleaning of contact routine but fault came back. I bought both pressure sensors off e bay not OE parts but changed them both anyway as they were reasonably priced with guarantee too . easy switch over and no need to bleed air, but be quick when removing off /on Fault gone.

 

[Nharris89]

I had the same fault it would come up on an intermittent basis, did all the cleaning of contact routine but fault came back. I bought both pressure sensors off e bay not OE parts but changed them both anyway as they were reasonably priced with guarantee too . easy switch over and no need to bleed air, but be quick when removing off /on Fault gone.

Thanks! Were you getting the 5e20 and 5e21 codes and replacing those sensors sorted it? I'm panicking I'm going to need a new abs unit now at silly money!!

 

[parabolica]

Did everything you've done so far - ended up replacing both sensors and just be done with it. Put the part number into Ebay and almost every option was coming from China or Hong Kong, but they turned up very quickly and fitting was straight forward, and have never seen the warning lights come back.

Only thing to be aware of when changing them is you have to take the front sensor off, then remove the one behind and replace it before replacing the front sensor - you can't get to the second one with the first one fitted. Make sure to seal your brake fluid reservoir with some clingfilm (cap off, clingfilm on, cap back on) to minimize the leakage from the pipes, esp as that first sensor has to be off for a minute or two until you get the second fitted.

 

[Nharris89]

Did everything you've done so far - ended up replacing both sensors and just be done with it. Put the part number into Ebay and almost every option was coming from China or Hong Kong, but they turned up very quickly and fitting was straight forward, and have never seen the warning lights come back.

Only thing to be aware of when changing them is you have to take the front sensor off, then remove the one behind and replace it before replacing the front sensor - you can't get to the second one with the first one fitted. Make sure to seal your brake fluid reservoir with some clingfilm (cap off, clingfilm on, cap back on) to minimize the leakage from the pipes, esp as that first sensor has to be off for a minute or two until you get the second fitted.

That's a great tip, thank you! Can I plug the front sensor whilst I remove the back one? Wrap a but of cling film around the opening there as well?

The sensors I've ordered are OEM parts but as you say from China, genuine parts are nearly £200 a sensor which is just silly money! They come with a guarantee and good reviews so I'm sure they'll be fine

 

[parabolica]

Issue is the first sensor sits exactly where you need to get your shifter/spanner to in order to loosen the second sensor off. If you're quick, you could have both sensors off and replaced within 1-2 minutes. Or, like me, forget to seal your brake fluid reservoir and struggle for a few minutes longer as you try to stem the flow of fluid with you finger whilst swearing at the replacement sensors not threading correctly

Edit: plugging the pipe for the first sensor once you've taken it off is a good idea, if you have something suitable.