Just had another look in Rave at the warning lamp functionality, attached below... According to this, what I am seeing (ABS warning lamp stays on, ETC lamp off, Brake warning lamp off) means: "ABS fault condition detected by ECU". In addition, I think your pressure theory might be out the...

Thanks @DanClarke - Good idea, that will help me debug the issue. Is this diagram from Rave? Thanks for trying that @kermit_rr, that confirms that my specific issue is most likely not sensor related as I don't get the TC light or traction failure messages. Sorry that your traction failure...

I will go and give that a try later today, great idea. I'm happy to drive it because the brakes work absolutely fine, but haven't tried to get ABS to kick in yet. Just to confirm, i've triggered ABS plenty of times before (I used to test drive vehicles at Millbrook proving ground, not on the...

As expected, new brake switch fitted and no difference unfortunately. Been for a drive and it's just the same as before. Anyone got any ideas what to check next? I'm considering changing the 4 ABS sensors themselves in case one of them has an intermittent fault which throws the light on the dash.

Whether or not the BeCM itself stores codes, I thought that when using a Nanocom it presents as if you're reading the codes from the BeCM. I don't own a Nanocom, but when @DanClarke connected his to my P38, the BeCM menus allowed us to see fault codes such as a P1668. I am probably wrong, I've...

Good point - after I've fitted the brake switch and put the seat back in place I'll take it for a drive to allow the checks to finish and see if there's any difference. Just to note, I've been reading on another forum (here https://www.rangerovers.net/threads/abs-fault.351667/) with very...

Checked all (I think 21?) connectors on the BeCM and they're all clean as a whistle... not a visible trace of corrosion on any pin. Reconnected the battery after checking and dealt with all the 'Window not set' messages and was then greeted with the ABS fault, which I was expecting. I'm at a...

Thanks all, Checking the BECM tomorrow, and fitting the new brake switch because... Why not!

Thanks that would be really useful. Good luck to you as well :)

I thought it would.. However with no faults showing on a Nanocom I am in the dark here... not sure what to try next!

On my model year there are 2 physical brake switches... One for the cruise control which has a 2 pin connection but also has a physical vacuum line attached to it to vent excess cruise control pressure. This is higher up on the pedal. And then the second one which seems to be the same switch...

Nope, never seen that message before. What would that indicate?

My thoughts exactly. As I see exactly the same outcome with the two ECUs, I'm wondering if there is a wiring fault somewhere and other systems are unable to communicate with the ABS ECU... for example, according to Rave there is a dedicated link between ABS and BECM... potentially the BECM is...

I tested the continuity of the main brake pedal switch today (the three pin one) to check that both of the internal switches were working (one is normally open, the other is normally closed). If i'm honest, I think there could be something wrong with it... the normally closed side seems fine...

Aha I didn't know that, it would be useful to see the values reported to confirm the wheel sensor states. Agreed - unless a sensor is outright dead, I don't see how the ECU could determine that it was faulty without the vehicle moving. I have swapped a 'tested and working' ABS ECU in, exactly...

A Nanocom showed no faults, and also that all four sensors appeared to have valid voltage readings. (2.31 from memory) so I initially thought the sensors were ok. How can you diagnose which sensor(s) are at fault?

Yes - getting the audible tone at the same time as the ABS fault message. In addition, I don't know if it was voltage related, but once or twice the message and audible tone were constantly happening every few seconds whilst driving... This made me feel like it was a wiring/connection fault...

Will do that tomorrow, thank you. Checked all the fuses today and they're fine, so BECM is the next port of call.

I've had the dash out already and everything seemed ok ☹️ The reason I had the dash out was because when I bought it I had a weird feeling that an "ABS fault" message should be accompanied with an ABS light, and at the time, it wasn't... Lo and behold, someone had taken the bulb out.

I have been for a drive at 20mph+ for a few minutes and it still happens the same as before unfortunately.