ToomanyVolvos;116553 wroteNo Temp on gauge is a classic 740/760 issue along with other issues on the display. Out of the several I have they almost all do it, especially with lack of use.
I've always found a nice little "technical tap" on top of the gauges brings them to life, as though they are just sticky.
My 87 never shows temp till I give it a gentle tap.
Hope that works.
I always try taping it. Didn't do anything baha