Am getting fault for brake switch. Tred new swich on grounds that they are common fault and inexpensive but to no avail.

Further investigation revealed that I am getting a residual 7.5 volts on one of the terminals on the brake switch connector that goes directly to the ECU even when it is disconnected. This should be 0v under these circumstances! (Autodata online has decided not to work so I cannot give you the actual terminal no, I had hoped to look it up while posting ) and I am assuming that this is causing the ECU to generate a fault code

It got too cold/dark for further investigation today but am wondering if anybody has seen this one before