I too went over a bump in a 04 disco and the three amigos came on with the brake light had it read and its saying right front wheel speed sensor. may be a stupid question but is that what I should start with. in some of the amigos post people are saying dealer tried to change wheel sensor like that's not where its at thanks gentlemen tim

 

besides the sensor you may want to check that Hub

 

Thanks you I will do that

 

Well this is wrong... It actually has three switches. On the Instrument wiring diagram you only get to see two switches, but there is a catch on that diagram. It shows header 0293 with a black triangle, which means that inside the header there are other connections not shown. If you navigate to the headers section and look at header 0293 (which is of type K109 - a 10-pin header in black) you will see the fourth connection, which goes into SLABS Pin9 on connector C0504.

So if your brake warning light is on it can come from SLABS too. Here are the two details copied together in a single screenshot:

The SLABS wiki https://blackbox-solutions.com/help/SM016.html says that:

Brake warning lamp: The brake or EBD lamp is a combined warning lamp with the low brake fluid warning and the handbrake warning lamp. The lamp is a red light with an exclamation mark inside a brake symbol. The SLABS ECU will illuminate this light if it senses a fault that will affect its ability to control the braking balance of the vehicle.

EBD - Electronic Brake Distribution. If you have an open diff lock and no EBD then if you slam the brake at let's say around 30 MPH hard, the car leans forward, rear wheels get unloaded and lose traction, without EBD (or ABS) rear wheels stop rotating especially on a wet road, the entire rear axle stops rotating, speed difference between front and rear axles gets easily beyond the threshold where the center diff suffers excessive wear, gets damaged or even self-destructs.

The Brake warning light is no joke.

 

The brake warning light is turned on by the slabs in the case of a hard fault i.e. no signal at all from the wheel sensor.

 

Turns out this is wrong too.


There was/is a signal it just evaluated as too low in a number of occurrences above a certain threshold (16?) to activate the brake light.
Pulled apart the front left connector, noticed it was rather loose and had some dirt in it. Cleaned up, deformed the pins carefully a bit with a pair of flat pliers, replaced the rubber O-ring, applied a tad of silicone grease, plugged back together, felt the healthy friction-induced resistance, cleared the fault.

Works fine since then (2 days only). I ordered a set of front sensors out of superstition

So red brake light with the 3 amigos does not necessarily mean that there is no signal at all, the weak signal condition occurrence count hitting the threshold does it too. Maybe other things cause it too, any condition that "will affect the [SLABS] ability to control the braking balance of the vehicle". Of course as deemed by the SLABS programmer