digital speedo/HUD

the speedo on my '92 coupe only comes on for a split second (once in a blue moon). I pulled out the cluster today to have a look for any loose connections… found nothing. I also pulled out and examined the digital speedo module… but that looked fine too (not like I know what to look for anyways).

any ideas what the problem could be?

my 89 did the same thing… usually when its warm outside… it was the HUD unit located behind the gauge cluster… about 300 bucks from nissan… but my buddy has one in his basement i think if you need?

so if the HUD unit is bad, should that be affecting the digital readout on the cluster? maybe I should’ve tried unplugging the HUD from the back of the cluster to see if it’ll work on it’s own.