This morning my HUD worked fine when I took a ride to the stores, made 2 stops, but on the last trip home, there was no HUD display. Looking into the projector through the windshield using a bright flashlight, it looks exactly like this pic.
https://www.ebay.com/itm/97-04-Corve...xe12:rk:7:pf:0

The mirror seems straight and level, not angled down on either side, not touching the bottom of the enclosure, and it does not move when the height control is activated up or down although you can easily see that little orange thingy sliding back and forth when you operate the control, so I know the motor is working.
Does this mean that one of the tabs (the one on the driver's side) has broken off? And this happens spontaneously without going over large bumps or potholes and not operating the height control at all in many years?
I can't see any indication of any display or light inside the projector box at night in the dark, so I don't know if that is working either. Is that something that can be seen from looking in through the windshield?
Every other thing in the car is functioning properly, all the other displays and computers seem fine. And my battery voltage is OK, 14,5V while driving, 12,4 V on the DIC if the car sits for days, and starts up instantly,

I'm really not looking forward to taking the whole car apart removing the dash to get at this so I'm grasping for straws and looking for any other suggestions before I resign myself to doing this.
And FWI, if it can't be fixed, replacements (all used) go for anywhere from $130-$350 if you can find them.
I've seen aftermarket HUD displays that plug into the OBD2 port that look interesting, for a fraction of the price of OEM and requiring no work at all. Sacrilegious but easy if all you want is to see the display of speed and engine temp.
So any help or advice is appreciated.

 

I hate to say it but I think you should be pulling the dash which I admit on your first try is not a very fun job. It's actually quite easy but I've only ever done it in a convertible where it's a little easier to get out. You just have to be careful.

I don't think I've ever heard of anybody here saying they had a projector failure so there is that. If you can check it now that it's dark outside and make sure there is absolutely no light coming from the hud projector, you know you have something more than just a misaligned mirror. If it turns into a worst-case scenario, let me know and I might be able to come up with a projector for you.

I would be checking fuses and wiring to the projector first though. And no I wouldn't Mickey Mouse rig it with some OBD2 projector.

 

I've taken off the console and the DIC to replace a bulb I found one day on the floor in the driver side footwell and replaced it with another bulb, but haven't pulled the whole dash off yet. Not difficult, just a time-consuming PIA.
It's not that I don't think I can do it, it's just that I don't want to do it. But I may have to. And I have to wait until i stops raining too.
There is no separate fuse that just powers the HUD, it also goes through the other computers and everything else is working fine. And why would wiring become a problem? To inspect any of that I would have to access the innards of the dash anyway.
The wiring to at least the motor is intact because I can see part of the mechanism (that orange colored **** barely visible in the lower right side in that pic of the mirror) moving fore and aft when I activate the height control switch, so I have to conclude there is a mechanical break somewhere, ie. the tab on the left side of the mirror has broken off. Anyone have any other ideas?
It's really annoying when things break spontaneously without any apparent cause. I guess old age just catches up to the best of us.

 

Any more comments or suggestions?
Anything else you can think of I should do or look at once the dash is off?

 

Yea, but if this is all that goes wrong with your car, I'd count your blessings.

 

I just replaced the instrument cluster on my car .I didnt want to either and have nevr done it before . I took my time and it wasnt all that bad

 

"Yea, but if this is all that goes wrong with your car, I'd count your blessings"

Ha. You're funny.
In the 5 1/2 years since I got it and and the 25.000 miles I've put on my 19 year old car (103,000+ miles now), I've replaced both belts and idler pulleys, oil pressure sensor, the hazard flasher, a bulb in the DIC that fell out, the high pressure power steering hose, front tie rods with an alignment, headlight bump stops, ambient air temp sensor, wiper blades, AC compressor and condenser, water pump (while the other AC job was being done), battery (twice), removed and cleaned the BCM of corrosion/salt to stop a battery drain, changed oil and filter 4 times, installed an LMC5, HID headlamps and 4-on harness, LED backup lights, front and rear backup cameras, brakelight flasher, cleaned and waxed it a few times because it got dirty, and it still goes like a bandit and rides like new, so I got to take it apart and fix the stupid HUD mirror just to keep it and myself happy.

 

You can't count the self-inflicted stuff. Much of that you elected to do. And I told ya I'd help you get a projector if you wanted it.

 

its easy but take time did mine 2 year back easier than the old c3 .. the hud is also easy fix just google it.. you will find it there if its displaying but not function ..it as a broken tap
but if no display then its electrical wiring,fuse,ground etc

 

The first 18 items on that list were not self-inflicted, they were things that died of old age and needed replacement. The later list of electrical things I added were my mods, not worn out items.

I will check in the dark again tonight to see if I can see any light inside from the projector, but I can't believe it's a wiring problem because, like I said, I can see the motor mechanism moving inside when I activate the height control, but the mirror does not move, which to me indicates a broken tab. So, K-Spaz, I'll let you know and thanks for your offer, but "let there be light".

 

I'm not trying to say it's wiring, only that it's not inconceivable. The reason I keep saying check for light is not because I think the wiring is off, but because even with a broken mirror, you'd see something in there if the projector itself was working. If there's no light coming out, there's no reason to bother with the mirror mounting fix.

 

Ya know, there is also the dimmer switch for it that might be telling the system to go dark. Have you checked that? I confess I didn't go back and read from the beginning again so if you've already covered that, just ignore this.

 

I have been out at night in total darkness, started up the car, and I cannot see any light at all looking into the HUD display from up above through the windshield. Turned on the headlights, still can see nothing inside the HUD.
And BTW, the dimmer switch is not the problem, it works normally on my dash lights.
Can someone on here go out in the dark and check if any light is visible at all looking into the HUD unit from above? I don't know if you are supposed to be able to see anything from this point of view, or it's normal to see nothing.
If your HUD unit is working you may see the display beaming up through the windshield, but I need to know if you can see any of the beam of light coming from the projector itself, or if you can see any light in there if your mirror is at its' lowest height adjustment so you don't see the beam display projected through the windshield.
Thanks.

 

I’m wondering if the little white harness that connects your HUD to the gauge cluster came loose. It’s at the top rear of the cluster and just pops out. It’s held in by friction, not a locking harness and comes out fairly easy whenever I’ve worked on my gauge cluster.

 

That's a possibility I guess, but then why can I see the motor mechanism moving back and forth but the mirror not move when that happens? That would indicate some mechanical break between the mechanism and the mirror, ie, the broken tab. What I would like to know is if anyone else can see any light inside the housing at night so I know if the projector is working. If the connector partly came loose from some of the contacts, than maybe the projector would fail to operate (no signal to it), but my motor mechanism still operates so that is getting juice. So at least then, part of the connector is still making contact. And that would come loose spontaneously? For no other reason than just to **** me off?
I still will have to take the whole dash off in either case, and just hope that I can fix the broken tab if that's the reason for the failure, and the projector still works. Won't know that 'till it's fixed and back in. But if anyone can look at theirs in the dark to see if there's any light in there, I'd appreciate it, just to know.

 

Sorry to bug you guys, but is there anyone out there who's not afraid of the dark in his garage or outside, or who drives at night, that can take a peek into the HUD unit and tell me if they can see any light in there when the HUD is on? Thanks.

 

Bump.
Anybody? Can anybody see any light in there other than what may shine up as the display into your face through the windshield?

 

Im no expert by any means, but the grand prix HUDs have the same issues. Theirs are mainly with the springs that hold the mirror within the adjuster. The springs break or pull thru the plastic that hold them. Whatever it is affecting yours, if all the fuses and harnesses are ok, you're still going to be pulling the HUD to do proper diagnostics. Good luck.

 

If it's the spring, is it possible to find something to replace it with, and where do you look? You won't get it from any parts supplier without spending $250-350 for a new HUD that comes with it.

 

I just went out to look into the HUD through the windshield as well as inside the car again, with car on and also with car running, and the mirror definitely is moving back and forth (angle changes) using the height control for the HUD inside the car. The problem is I have no display at all, no light can be seen inside the unit, ie, there is nothing projecting onto the mirror. The HUD vertical dimmer switch is inoperative, nothing happens when you slide it up and down multiple times, the rotary dash dimmer below that for the IPC works fine. Is there a way to reach or access the HUD dimmer switch from underneath the dash, say by removing the bolster under the steering wheel, or to access this you still have to remove the whole dash to get to it? I'm hoping that maybe it's just a connector that vibrated loose and my repair will be real easy and quick. Wishful thinking and fat chance probably.
I'd hate to remove the HUD unit and disassemble it only to find the problem is somewhere else.