I need to access the plugs at the back of the head-up display control unit to troubleshoot the system, the speedo is blank but the speed sensor is good. Do I have to remove the glaresheild to do this and if so is it a real hassle and do I need any special tools to flip the pawls and latches?

 

Should have said........91 240SX SE to clarify which model car.....any ideas anyone?

 

it probably is a capacitor on the speedo that is bad. Common prob for the digitals. To get to it just use a screw driver to carefully depress the tabs and work the face of the gauge cluster off. I am assuming you have the gauge cluster out? As for the hud you have to pull up pretty hard to get the HUD cover to come off then you can undo the screw bolts that actually hold the hud in. I will try to post some pics of the capacitor I replaced on mine to get working again.