MCP indicator in SPEED button not lighting up after touch and go

[Hakkie]

Did some touch and go's last evening at LDDU. Noted that the indicator in the speed button on MCP did not light up after pressing it (at approx 2000ft) after the touch and go. AT did kick in and worked, also indicated on PFD. Not sure if something is wrong here or if it's wrong expectation from my side that the indicator should be on in this case.