TC can be disabled, this puts a light on the dash also.
a bit of a long shot but i wonder if the system could be confused? try disabling it and re-enabling it
ignition on/engine off - press pedal 10 times in 5 seconds, you should get a beep and a message on the LCD. start and drive at 10-20mph and it should turn back on again and the dash message should go away. do the lights go off also?
 
thank you for that feedback! But
I was in nanocom EDC-WABCO D- UTILITY-using the Power Bleed, Modulator Bleed and brake test functions
The TC lamp went out so I took her for a spin to see if the ABS light would go out and it did for a moment, then I braked at the roundabout and both came back on!
I had also been cleaning the relays 15 green and 17 black
I noticed that the green relays seemed warm, warmer that the others!
Still, a brief glimmer of light through!
I think a new relay!
 
For the connections from ABS to BECM, there are three wires in addition to the K-Line to the diagnostic connector. Looking in the Nanocom & BECM SID documents, these are what the signals are for. It is not clear in any of the documents if the ABS & ETC lines are actually serial data, or simply a set of voltages that represent faults ?

Might be worth checking all three ??

Wabco-D Nanocom DocBECM SIDDescription
Pin-3 = ABS Warning LampPin-11 Road Speed ?Square Wave 8000 pulses per mile.
Pin-17 = ETC messages and warning lampPin-12 Traction Control & ETC LampModulated 0-12V depending on message
Pin-18 = ABS warning lamp/message Pin-10 ABS warning lamp/message InputModulated 0-12V depending on message


1748941095235.png
 
Another thought or two. Does the handbrake light work ? Maybe a bulb failure there causes the other two to light up ?

Also have you re-checked wheel bearings, CV joint & the sensors are properly pushed in ?
 
the hand brake light works properly
I begin to think it is the brake switch that is causing the problem.
I had the TC light go out today so got her out and the ABS light went out as is should, as soon as I touched the brakes the ABS/TC lights came back on with the messages also!
I have replaced the brake switch but all is not well with the brake system me thinks
 
If you re-test the brake switch using a multimeter, you should see the 0-12V & 12V-0V switch on both contacts immediately.

Nanocom takes a few seconds to register the state, hence why you might sometimes see open-open & closed-closed. Remember it's reading them in sequence, not at the same time.

Also check the ground for the ABS ECU and the Modulator. They are in different places, so if one is not perfect that will cause strange behaviour.

Given that everything else seems to be correct you might need to re-bleed the system. Do not use the Nanocom, but get a helper & follow the RAVE procedure exactly. FYI the guys at BBS say you should always complete the manual bleed in RAVE before using the Wabco power bleed anyway.
 
I have bled the brakes according to rave, and subsequently checked them. They have no air in the system.
For now I will focus on the brakes as I think there in lies the problem
 

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