Does anyone know where another data line is to tap into for the hud unit. I got the display up/down, dimmer, and the led to display two flat bars. Can another help me out with this problem. I soldered the wired for the hud unit direct to the circuit board where the connector should be.

 

May want to PM this member and pick his brain for the answer.

http://forums.corvetteforum.com/show...d&forum_id=103

 

anyone...ttt

 

Is there a data ipc line that can go straight to the hud?

 

Do you mean your cluster didn't have the little white connector in the top and you soldered to the board instead? Your not talking about the cluster to switch cable, right? If so I'm guessing that won't work. I'm guessing your cluster won't have the firmware to drive a HUD. It is my understanding that the data that drives the HUD is generated by the cluster not the class 2 data stream. So the cluster will gather all the data from the car then pass what ever data to the HUD that the HUD needs to see. It appears to be three data wires between the cluster and HUD. I didn't probe the data to see what it looked like but it seems like two data and one clock lines. My guess is the cluster generates the clock and there is one data line to the HUD and one data line back from the HUD to the cluster. I'm pretty sure the HUD does not use the class 2 data stream, I'm thinking it is just the HUD and cluster on those data lines. If this is your case you probably need a newer cluster. It appears that GM always planned on a HUD but didn't have it ready in time for the early years. All or most clusters have a place for a HUD connector but many older ones don't have the connector and I assume the firmware either. Later years, 2000 or 2001 (can't remember which) all clusters had the connector and would drive a HUD even if the car was not equipped with a HUD.

Hope all that made since! Good luck!

 

If you check the link above, you'll see it will work if you simply wire the HUD harness directly to where the connector normally would be on the IPC. That's why I posted that link - the member who posted it soldered the HUD harness to his non-HUD IPC and got it to work with the HUD unit he bought. Try PM'ing PLYFSTR and see if he can help you sort out your hookup.

 

Well I read the post you linked to before I started the hud install. I wanted to try it. Got most of it to work. I sent that guy a pm a week ago and still no answer. The only thing I did notice on my cluster where I soldered the connector was that there was a white outline that I think said r5 and had solder points and nothing attached to it. What is crazy is that my cluster had the provision for the 11 pin hud harness. Plus the cluster did dim, and change the hud mirror postion. All I am getting right now is 2 solid bars displayed on the projector. If I can figure out what and how the clock, strobe, and data lines work I my be in business.

 

Here are the IPC schematics.

 

The mirror control and dimmer is pasted straight from the switch (through the cluster) to the HUD, the cluster does nothing with those lines. If you have a scope, probe around on those other lines and see what you can find. The best I remember there is one line that will have a square wave on it all the time, I pretty sure it was sourced by the cluster. There was another line that had a lot of data on it, you could see it was random pulses, then the last line seemed to have very little data on it, just a few pulses now and then. Sorry I can't help more, I wrote all this stuff down pin outs and everything when I installed my setup then when I got done I was going to document some of the stuff I found while doing the project and I couldn't find my papers, they never did show up I have no idea where they went!

Good luck

 

I'm guessing it may work on some but not all. I'm guessing it is a crap shoot if it will work or not. Probably the closer to the years that had the connectors the better the chance of working. I find it hard to believe they would put everything in there to run a HUD except the connector, just don't make since. That means they would have to build, track and inventory two entire different items just because a 10 cent part, just don't make since. I could see where the projects evolve and the firmware is updated and HUD ready then the order comes down the line to start installing the rest of the parts. I could see where there would be an over lap where they may just be missing the connector. I'm still guessing they all won't work. Good to know some do though, always worth a try!

 

I think you're right. I have a '98 which I added a HUD to. At first, I bought a 2000 IC and was going to remove the white female projector fitting (from the main green colored circuit board). I was going to solder the white connector to my '98 cluster circuit board. The reason being, I would save $$ on having the odometer reprogrammed and I knew everything worked on my '98 cluster. When I compaired my '98 circuit board vs. the 2000 board, the 2000 board had resistors and chips installed in the wiring up near the white female connector, whereas, my '98 was missing these items. I quickly decided not to mess w/ it and had the 2000 programmed to my mileage. I did however, install the 2000 circiuit board in my '98 cluster---I worked great.

If you've done any research on instrument clusters, you'll note there are several different part nos. for these clusters. I'm not talking Z06 or anniv. clusters either. There are several different part nos. for non HUD clusters. Why??? Wouldn't you think they'd all be the same number?? That's because, as you suspect, some of these non hud clusters can be used for HUD, while others cannot.

Oh well, I've rambled on long enuf. I just wanted to add my 2 cents into this story---maybe some of this info can help someone.

 

Thanks guys for your input thanks.

 

Very interesting, BiggieBoy. You wouldn't happen to have taken any pictures detailing the differences in those two boards and IC's, would you? Would be interesting to see those side-by-side.

 

No pictures Patches. Unfortunately, I never thought of it at the time. The only thing I can add is: my '98 IC was GM part #10411393.

 

Just curious what finally happened with your HUD mod attempt?

 

That was 10 years ago. Hopefully, they're still around. GL . . . . .
It's ok. You get a few since you're really new here. And to be honest with ya.. there are a lot of threads that never get completed so we're all left hanging...

 

Yeah I know that was a 2005 thread and people can be here one minute and gone the next (as in 6' under), but I like to know if people that venture into major electronic related mods that have no apparent technical knowledge eventually accomplish their goals. That one seemed like a rather lofty one.