digital Speedo unusual problem

[1989coupe]

I have an interesting problem. I have an '89 coupe and recently the speedometer will flash on and off when I drive it. Any ideas? I can fix it if I have and idea of what exactly the problem is.

[navysnail]

the hud unit is probobly going out, either that or the sensor.

hud faliures are verry common among 240's so you may just want to convert to analog or just use your tach

[1989coupe]

Can the HUD unit cause the entire speedometer to act like that?

[wangless]

its probably one of the little resistors on the digital cluster itself iirc, read it somewhere on 240sxforums.org

question, when the flashes on... does it tell you your speed ? if it does, then your speed sensor is working, and its just the digi cluster thats messed up.

for me i had both the cluster and speedsensor mess up. when my hud actually worked, which was only twice since i owned the car, the speed would be at 0 mph/kph. hoped that helped a bit...

and do some searching as well... there are tons of threads discussing broken HUD