Hi folks,

For a while now I've had a project under development to produce an upgrade for the windshield wiper system on Series 1 RX-8s.

It makes the intermittent ('INT') mode of the wipers speed-sensitive, such that the wiping interval is extended as the vehicle slows down and comes to a stop. That means there's no need to touch the controls if, for example, you had your wipers going on a fast setting, but don't want them still doing that as you sit at a traffic light.

There's also one other improved feature it has, which is to alter the behaviour of the auto-wiping when the windshield is washed. As standard, the wipers only activate after you hold the washer switch for approx. 2 seconds, and then only gives a single wipe. I was always frustrated that this wastes far too much washer fluid, and a single wipe is never enough. So, it changes the behaviour so that instead the auto-wipe activates after holding the wash switch for less time (around 3/4 sec) and wipes 3 times.

The upgrade is done by replacing the entire circuit board on the wiper column stalk assembly, by de-soldering the old one and soldering my new replacement one in its place. The only other thing that is required is to run a single extra wire for the VSS (Vehicle Speed Signal) from the harness behind the audio head unit.

Here are some pics:






(Pictures from when I was bench-testing. Ignore the extra stuff plugged into the board; that was only for programming and debugging.)

So far I've been running it on my own car for a couple of months with great success, plus another UK owner's club member here will shortly be testing it in his.

I've been wondering whether it will work as-is on North American model RX-8s. I think it may well work just fine, as the only difference I've seen - according to wiring diagrams - between LHD and RHD models is that a single wire on the connector is a different colour but same function.

Hope you guys across the pond would find this interesting. I can post further about it if you want to know more.

 

Get a video demonstration so we can see its functionality when you can, it sounds like an interesting concept and you may end up coming across someone who might be able to give very constructive input.

 

Yeah, doing a video is a good idea, but I'd have to borrow a camera or get someone else to do it. The only device I have to record video with is my phone, but I don't have enough free space on it to take more than 30 secs of video.

One of the neat things about my upgrade is that all the parameters governing the behaviour of the wipe intervals timings, speed thresholds, wash auto-wipe count, etc. are all stored in EEPROM, so they can be customised without changing the code.

For instance, here's my default speed-interval mapping:



It specifies what interval setting to use when the vehicle's speed is at or below each threshold (e.g. for switch setting = 1 at 8 mph, actual setting used = 4).

 

That sounds interesting but once the light changes you will want the wipers to wipe.

 

Yes, of course, that's why the wipers will resume their set speed as soon as you get going again.

 

This is pretty cool - I've been wanting to find more ways to make my RX-8 a little more modern Sports Luxo feeling, i feel like this is one of those small details...

When/how would these be available?

 

At the moment I have a handful of prototypes being tested by a few people. I don't have any more available though as all my parts have been used up, and I don't have immediate plans to assemble more.

However, there seems to be growing interest in this, so if there were enough people committed to getting one of these upgrades, then I could consider having a small batch professionally manufactured. It would have to be around 20 units to be economically feasible though.

As for a price, I haven't thought too much about that. If sold as a straight-swap wiper stalk unit, it partly depends on how much it costs to acquire donor wiper stalk assemblies - prices vary. On the other hand, it could be supplied as a DIY kit of circuit board only (without wiper stalk). That would certainly be more amenable to international shipping (don't forget I'm in the UK), but would place more requirements on the end user (need for soldering skills and equipment, plus the need to take characterising measurements with a meter for calibration before despatch). A figure I've been tossing around in my head is that of somewhere in the region of the price of a tank of gas. I don't think people would be willing to spend much more than that. Probably half for a board only DIY solution.

Anyway, if anyone else reading this is interested, please post here or send me a PM.

 

I'm down for the DIY option.

 

I'd be interested in retrofitting the rain sensing wipers from the 2009+ cars more than this mod. This is intriguing, but probably less important to me given that I live in San Diego where it rains 10-15 days a year and my 8 is now a play car rather than a DD.

 

It would be one hell of a job to retrofit the auto wipers from a series 2 car.

The main problem is that a single control module runs both the auto wipers and the auto lights, so to start with you would need to alter both those systems at once. Then you'd need the rain/illumination sensor on the windshield, plus both newer lights and wiper stalks. And that's not even mentioning the fact that a whole bunch of harness wiring would need changing or adding to.

A nice concept, I agree, but completely infeasible.

 

I figured as much. Wanted some of the newer tech from Series II retrofitted onto my 04 when they came out, and after getting my 8 running again after 2 ½ years and driving a 2014 Focus ST in the meantime, REALLY got used to keyless entry/start and auto headlights. Getting back into my 8 and needing to put a key in the ignition and turn lights on/off suddenly became a PITA.