HUD question 89' 240sx

[sidewaysil80]

I just picked up an 89' coupe from the 2nd owner. Car is a flawless automatic with one and only one issue. The HUD/gauge cluster work and are super bright, there is no flickering or blinking like some of the known issues. However, they are both displaying "0mph" regardless of driving. I was leaning towards the speed sensor in the transmission, but prior to dropping $50-100 on it, I wanted to check and see if this solved the problem for anyone else. I'm hoping it's not an issue with the actual HUD as some past threads seem to insinuate.

Thanks!

[apex128]

Check to see if your speed sensor is even plugged in. Sounds dumb but my speedo was broken and all i did was plug it in. Also make sure that there is a good connection on the plug. I had to clean mine out.