Ph2 172 clocks and brake lights not working after battery change

[moorin]

Basically fitted a new battery to my mk2 ph2 172 and when I came to start it back up the tachometer needle and numbers lit up but needles are not working on anything. Also my brake lights have stopped working. I've heard leaving the negative lead off for two hours could reset the ecu but Is this true?

 

[moorin]

Bump, fitted new brake pedal sensor and that hasnt helped. Also left ecu to "reset" if there is such a thing, might try the old battery just incase. Sounds like it could be a ground problem any ideas needed please