UB3 Dash Project

[Henry]

Hi guys,

 

My first post on these boards, so I like to start by saying hi! I have browsed around the board and it seems like a nice helpful atmosphere here.

 

Now what brings me here? Well, I'm very interested in electronics and would like to attempt to build a custom dash for my car. The best looking dash cluster I've seen is that of an Oldsmobile Cutlass Supreme, a wonderful looking piece of kit. (this is the one)

 

My plan is to try and make the cluster to work with my current setup. The car is actually a Peugeot 205 (I'm located in the UK ) It's defiantly a pretty large project but I'm hoping with your advice and input I can make it happen.

 

Obviously before I embark on this project, I need to see how feasible it’s actually going to be and try and predict some of the problems that I'm going to face.

 

Of least importance are the lights around the outside of the cluster, such as the engine service light and low coolant light. I will ignore these for now.

 

My priority lies with the speedo, followed by the tacho and then temp/pressure gauges. I have read the article on the main site and I can already see a few bits and pieces that need to be overcome:

 

1) What is the "Bi-directional Serial Data Link between Cluster & ECM" actually used for?

 

2) Somehow I would need to emulate the "Vehicle Speed input from ECM." Could anyone provide any info on the type of waveform needed?

 

3) Am I right in thinking it wouldn't be that hard to get the temp/pressure gauges going as this simply operate by measuring resistance?

 

Can anybody see any other hurdles I haven't spotted? The current vehicle features cable driven speedo (although I know a digital sender is available) and a ECM driven tacho (unsure of the waveform but I know it pulses faster with higher rpm)

 

Thank you for your input, and I hope you don't think I'm too mad

[Henry]

Thanks for the reply Dave,

 

I will definitely get a manual from eBay - good idea. Is the factory manual the best for wiring diagrams? In the UK the main source of info is the haynes manuals and I see they make one for this car too.

 

I see the tacho being the biggest problem, as it looks like I'll need to transmit OBD1 serial data somehow. Erk...

 

Cheers,

Henry

[Henry]

I have found a post that is EXACTLY what I need:

 

http://w-body.com/forum/viewtopic.php?t=18216&postdays=0&postorder=asc

 

So I'll chew that over and see what happens...

[Henry]

Well, after some thought and a chat with others I'm considering my options.

 

Someone from the forum designed a microcontroller that does the exact job required. How ever its way above my price range ( :bawl: ) so that leaves two options, design my own microcontroller or use the ECM from the car.

 

I think I'm going to for the standard ECM route, hopefully it will run with just a 12v and a ground connected.

 

Any thoughts?

[Jcrow]

The tach gets info from the orange serial wire, it also gets the red-line information

[GnatGoSplat]

I think I'm going to for the standard ECM route, hopefully it will run with just a 12v and a ground connected.

 

Microcontrollers are actually pretty inexpensive (less than $10), but programming it has a pretty good learning curve.

 

Installing an ECM should work, but you will have to convert the pulses from your tach signal to one the ECM understands. I forget what that is, but I think it may be 3-negative pulses per revolution. A 1227730 ECM can be installed inside the car and is smaller than the 1227727 which is designed to be installed underhood, but both ECMs are electrically the same. Many engines used the same ECM, so it would be best to try to get one with a PROM from a 2.8 or 3.1 car.

[Henry]

The tach gets info from the orange serial wire, it also gets the red-line information

Thanks for confirming that

 

Microcontrollers are actually pretty inexpensive (less than $10), but programming it has a pretty good learning curve.

Indeed, my current knowledge of them isn't good enough to build what I need so I think the ECM route is the best idea.

 

I need to find out more about the exact tach signal and also the speed signal...

[GnatGoSplat]

I can probably find out the tach signal for you.

 

The speed signal is DEFINITELY 4000 negative pulses per mile.

[Henry]

GnatGoSplat, that would be a massive help if you could! Then its just up to me to emulate the signals going into the ECM

 

Thanks again,

Henry

[Baddflash]

And I thought I was pushing it putting that dash in my Lumina. That's quite the job you are taking on here.

The speed and tach(redline) are your biggest issues for sure, you will have to hope that Renault would use similar enough technology that you can feed the signal directly to the ECM, cause I imagine it will be costly to convert the signal to something you can use.

I never got into this when doing my swap so I can't help ya there, I will give ya one piece of advice. With the warning lights pay attention to which go on which common line cause they aren't all grounds, some lights (ie signals) have a positive common.

 

Personally I would try and build/buy something to monitor those couple inputs and drive serial data signal to the dash, may end up being cheaper in the end.

[Baddflash]

This should help ya with the speedo.

 

http://www.w-body.com/forum/viewtopic.php?t=28311&postdays=0&postorder=asc&start=0

[stockgp]

i think if you try searching there was another guy a while back that wanted to put the ub3 in his hot rod project. and i'm fairly certain someone on here provided him with the tach signal expected and vss puls info as well.

 

edit: hope this helps

 

http://www.w-body.com/forum/viewtopic.php?t=18216&highlight=tach+signal+expected

[Henry]

Thanks for the help so far,

 

I'm waiting for an electronic VSS to arrive at the moment.

 

I don't actually have a UB3 cluster yet so I need to source one. Good old ebay has come in handy and I was going to bid on this. However, the guy selling it isn't that helpful and won't post to the UK. I also asked him the mileage on the cluster and he didn't reply after reading I wanted it posted to the UK. Could somone ask him the mileage on the cluster? I don't want to pester him any more but would like to know...

 

I'm thinking I could get it posted to one of you guys and then you could post it to me - anyone willing to do that?. I would cover the costs. It takes an element of trust I know, actually I tried something similar before and the guy I got it posted to disappeared :?

 

Very greatful for your help,

Cheers,

Henry

[dsgrntld187]

I have a remanufactured UB3 I bought for my Cutlass but never used I could sell. Make me an offer if you want it.

[Henry]

I have a remanufactured UB3 I bought for my Cutlass but never used I could sell. Make me an offer if you want it.

That would be useful, could you keep a hold of it - I'm waiting for this VSS to arrive so I can see if its going to be capable of driving the UB3 speedo.

 

Cheers,

Henry

[dsgrntld187]

I'll hang on to it, I might temporarily put it in a 92 Cutlass but I'll still sell it.

[Henry]

Well to save you the hassel of that I might as well buy it off you, how does $40 sound? I can pay P&P, I don't think It will be that much (I hope!)

 

Do you know how many miles the cluster has on it? I know from previous threads its possible to accelerate the mileage forwards but not backwards - which could be a problem.

 

 

GnatGoSplat - Have you managed to find any tach info yet?

 

Thanks a lot,

Henry