CAN to Relay/Mechanical recommendations

Hi, this is my first post so apologies if I miss anything obvious:

I have a Porsche 997.1 GT3 Cup car that I've fitted an AiM SW4 wheel on. This has given me a large range of button and toggle options via CAN which is great, however, many of the things I want to do translate into mechanical/analog outcomes like headlight flash, wipers and so on.

I'm curious if there is a well known option that you folks recommend to convert a CAN signal to an analog output ie a relay or voltage change etc.

I've done some Googling and found a few hits, but they weren't names I've heard of and thought I would shortcut the trial and error by asking here.

Cheers,

Ben

Ben,

You're effectively describing a PDM, and especially given this is a cup car, that's the route I'd go.

It takes the place of relays, fuses, adds more advanced circuit protection, logging, logical control via data received over CAN, and PDMs can stream data on the status of the controlled items back to a logger via CAN bus.

HPA has a great PDM course if you haven't seen it yet:

https://www.hpacademy.com/courses/pdm-installation-and-configuration/

Yeah I guess you're right when you look at the problem statement. I actually have an AiM PDM32 sitting in a box but that's meant for an mx-5.

If it wasn't for the cup car wiring and fusing to have already been done to a great level I'd definitely consider pulling out that fuse box and redoing it all with a PDM. All I'm really wanting to do is a slight augmentation, so a full PDM redo feels overkill, although I could run a PDM in parallel for only the things I want.

Which is kind of where I ended up as I was looking at one of these - https://blinkmarine.com/products/keybox/

It can run in a slave mode talking CAN Open, it has 11 relays at 10A and can even do some basic PWM on 2 channels, and is much cheaper than any Motorsport PDM I've seen. I believe this should do the job after getting my AiM wheel to send specific CAN messages based on button presses.

If you think I've missed something obvious in that approach please let me know, otherwise I'll pull the plug on it and I can update this thread on how it went.

Thanks for your response, Mike!

Ben,

If you said it's a budget hobby project, there's no need to diagnose or resolve faults in a timely fashion, then non PDM options would have come to my mind, and of them, the Keybox looks very interesting for the money.

I've never had an issue with a Blink product, so I'd bet Keybox is great when compared with similar products. I did a forum search and it seems you're the first to mention the Keybox, so we may not have a forum user with direct experience yet.

That said, any time you use standard fuses, mechanical relays, they can be susceptible to jostling, vibration, and cycles of use. I would expect it to work out of the box, and then service life would be a question mark. Sometimes it's something as simple as the contacts on a relay or fuse loosen up, but what impact does that have?

I also think what happens if a fuse blows due to random electrical anomaly while reconnecting something, jump starting the car, or otherwise. There's no diagnostics, no resetting that, no warning that anything is wrong. Does the driver end up losing a session or more when they realize something isn't working?

Since you said Porsche Cup car, I went straight to PDM for a few reasons, some of which go beyond device specs.

First, anyone with a Porsche Cup Car can afford a quality PDM (not one of the unreliable PDMs).

Next, many people chose to specifically buy a Porsche Cup car over a different track car because of their reliability, and they want to retain that reliability, so they can enjoy their valuable time at the track. I believe a quality PDM makes sense in terms of reducing likelihood of issues, being alerted to issues, speed you can diagnose issues, and that all provides value that's meaningful to a car owner.

I would install a PDM for all auxiliary items so the factory wiring can be left unaltered. I wasn't suggesting a full rewire unless there are other reasons one is needed.

I haven't used them, but the Kaizen relays look interesting if you only need a couple. If you need several circuits, then I'm back to my PDM suggestion.

Whatever you decide, I hope it works out great!

Thanks Mike, all good points.

My cup car is an '08 and while I can afford a PDM I'm not in blank cheque book territory as this car is just a track day car, unfortunately there's no competitions here I can enter it in.

So I guess I'm more on the hobby side than serious reliability of a competition car.

I think I'll give the Blink Keybox a go, if nothing else I can report back on success or failure for others.

I'm going to mark this resolved, thanks again. For anyone else reading this that wants to know about the Keybox outcome feel free to PM me.