Hi guys, I was wondering if anyone can help me. I just bought a C05 HUD which I am looking to fit on a Ford Escort and was wondering if anyone could supply me with any technical details about the RPM and speed input signals that the HUD requires? Any help would be greatly appreciated

 

It will be tough to retro fit a C5 HUD in any other car!

The C5 HUD only has a single cable connection. Eight to nine conductor cable the best I remember. All data and power is feed to the HUD through that cable from the IPC (Instrument Panel Cluster). The HUD and IPC communicate via a serial protocol. I think this may be 3 wire SPI protocol but have I have not verified that for sure. ALL the data displayed on the HUD is gathered and formated by the IPC and sent to the HUD. The HUD does not accept any signals such as speed pulses, tach pulses, or analog signals from any thing in the car. It only receives formated serial data gathered by the IPC, from the IPC. If the HUD is powered up without being connected to the IPC (or not getting any communications to the IPC) it will simply display two dashes in the center of the two digits where the speed is displayed.

The signals that I remember the HUD gets (in no certain order):

12VDC+
Ground
Intensity 0-12VDC+
Page
Motor Up
Motor Down
Data Signal
Data Clock (or possible device select)

Good luck with the project!

 

Additionally, all the data coming into the IPC is on a digital bus, coming from the Powertrain Control Module (PCM).

I think you'd be much better served getting an aftermarket HUD and adapting it to your Escort.

Have a good one,
Mike

 

Thanks guys

 

Hi guys I have managed to get hold of a HUD cluster as well as the projector. Its my limited understanding that the cluster takes the speed and rpm details from the IPC (ecu) using the CAN protocol? If this is correct, if I had an aftermarket ECU in my ford which supports the RS232 protocol (I have an AUTRONIC ECU) would this work? Or would I need the C6 HUD for CAN

 

GM used J1850 VPW for their protocol on the C5. Much (not all) of the C6 data communications is CAN. Here is a pinout I made while working with a 2001 C5 IPC. I think it is pretty accurate but not 100% sure. For the speedometer the IPC expects 4000 pulses per mile. Not exactly sure on the tach signal from the PCM, from my experience it don't seem to be an exact pulse per fire (4 pulse per revolution) like most tach signals. In at least one place the GM C5 manual makes reference to the tach data comes over the data buss, I think this is incorrect. The tach data is on the buss, but I think the IPC displays the tach from the pulse from the PCM. The data buss is used for illumination controls, DIC message display, some warning lamp controls. The IPC communicates with most other computers on the car. For example if the IPC don't hear communications from the brake computer for a second or two it will by default display "Reduced Power" on the DIC. The IPC also communicates with the BCM (Body Control Module) for dash illumination and other stuff. The IPC communicates with the PCM for information to display such as oil pressure, fuel level and water temp.

There is a company that sells an "ELM" chip that will interface RS232 to the J1850 that GM uses. I think you can buy them from scantool.net or something close to that. It will require sometime of interface to format the data the way the IPC wants to see it, but with you should be able to run a C5 cluster in about any car. It probably won't be real easy though.

I can't remember the members name but someone is retrofitting a C5 dash and IPC in a C4. You might look them up and see if they may have more info on running the IPC standalone.

 

Thanks Speedyz thats great. Ill start scouring the forum

 

Seriously?

 

 

Yes its a Ford Escort Cosworth 4x4 rally car. An extremely rare and prestigious rally car, and cost in excess of $180,000 to build. I wanted a HUD to allow me to keep more time with my eyes on the road. . I am just on here for some friendly advice, Sorry if this post offends you. How much is your corvette worth by the way?

I am just glad there are some nice and respectful people like Sppedyz on this forum who is willing to help someone like myself rather than pick holes, and try to ridicule them when in fact they dont know the whole facts and assume I have some shoddy motor. Well I dont

 

Don’t take it too seriously; nobody is safe on this board. There’s always ribbing going on in good fun with quality info. Good luck on your project, it sounds like a fun car!

 

Cheers Ill keep everyone updated if I can get it to work lol!