Dreaded DTC Lights - HELP NEEDED

[Court1987]

Hi all,

I've had the dreaded DTC 2no lights come up on my car and i cannot get rid of them. ill list our what I've had done to try and get rid of them and for general maintenance.

1. I've has all ABS sensors changed
2. I've had front ABS rings changed
3. I've have all bearings changed (front and back)
4. Had the car fully tracked and aligned

Pressure sensors are recording but pressure sensor is recording negative bar so I will change this later tonight.

This is urgent as I am going on the track on the weekend which is not looking like very good weather and I'd rather have some safety features on for myself and other track users.

 

[brillomaster]

brake pressure sensors are easily changed, and cured my trifecta of warning lights. get that done and report back tomorrow, as you say, you've already replaced the abs rings and sensors.

 

[Court1987]

Would you consider a negative bar on the brake pressure to be normal? its on sensor 2 which I believe to be the nearest the bulkhead.

 

[Chris_D]

This is urgent as I am going on the track on the weekend which is not looking like very good weather and I'd rather have some safety features on for myself and other track users.

I'd suggest that you come accross as not-altogether confident in your own abilities and avoid the track entirely if you feel the need to have traction/stability for you or others, especially in the wet!

 

[Court1987]

not very helpful there Chris. I've been on plenty of track days with my various cars in the past. On this instance i have my younger brother who is only just getting into it wanting him to be safe is not unreasonable and even though i worry about his lack of track experience its about having fun right?

 

[poss]

I had this very issue on my Zed today - but it went away after a restart.

And that's very similar behaviour that I had in my E46 M3. I fixed the M3 by disconnecting and re-seating the ABS electric harness connector a few times. This is the first thing you should try before replacing parts (haven't located where the equivalent connector is on the zed yet tho)

There's a very useful article on diagnosing the cause of this on the E46 forums - which should apply to the zed too as I believe its the same componentry (i.e.: is it a wheel sensor, pressure sensor, or bad connection issue - each will manifest differently)

 

[Court1987]

Brilliant, thank you!

 

[Court1987]

Would you consider a negative bar on the brake pressure to be normal? its on sensor 2 which I believe to be the nearest the bulkhead.

Just an update, i have replaced the sensor and the problem persists.

 

[enuff_zed]

Would you consider a negative bar on the brake pressure to be normal? its on sensor 2 which I believe to be the nearest the bulkhead.

Just an update, i have replaced the sensor and the problem persists.

I wonder if [ref]colb[/ref] may have some thoughts on this?
Sounds like you've changed most of the components, so it could be the wiring/connections between them?

 

[colb]

Not seen a negative reading from either of the two pressure sensors on the master cylinder, mine had a code set, looking at live data both appeared to be working ok but looked like one was giving lower reading than the other. Changed out thaqt one with a cheap ebay sensor that cost £12 and that resolved my problem and code. I have seen that an issue can come up if the plugs for the sensors are mixed up and put on the wrong sensor. From my experience with these I would suggest that if there is a mismatch of pressure between the two sensors its going to set a code for the iffy one that being the lower pressure one. Changing my one sensor fixed it and have another in my spares stash just in case the other one fails.

 

[Court1987]

Another new pressure sensor and taking off the ABS sensors and reconnecting them has cleared the issue.

if any one is interested on how the car did on the track see link below.

https://youtu.be/6jkC7EcJwjw

 

[Mr Tidy]

if any one is interested on how the car did on the track see link below.

That looks like a fun day out.

I love Donington, especially the Craner Curves!