[RedBaron]

On another forum, there was a discussion some time ago about disabling iStop using a 3rd party plug/play unit from mikstoreph.com. I searched the web for how this worked, and it seemed, from a couple of pages I saw (below), that the I-stop button is just part of a resistor ladder along with the other buttons. The workaround to disable the i-stop is just to use a relay to quickly bridge the two common switch wires coming out of the switch box with a suitable resistance (~85 ohms) right after the car starts. I like the method in the second link that stores the last state so you can enable or disable the I-stop when you like. I have done many projects with these microcontrollers, so wouldn't be hard for me to do (now I know how the button works):

How to disable the Mazda i-stop system

An explaination of the HTTP Cache-Control header

no-cache.net

born2bastel » Start-Stop Automatik deaktivieren mit Memoryfunktion

www.nicomania.de

HOWEVER, since then, I spent the $30 for a 24hr access to the Mazda workshop manuals and downloaded all the CX-50 schematics etc. I also pulled and opened up the pushbutton switch unit from my car. Turns out that the info I thought I knew (from above) is wrong. The newer cars actually use a microcontroller on the switch circuit board and communicate the switch presses and LED lights via the Canbus, with only 4 wires out of the box to handle the 5 buttons and 2 Leds - see pics below. So, the DIY method of building an iStop disable box is much more difficult than I had earlier thought and would have to emulate the Canbus protocols. So, I've given up on that idea and just ordered the mikstoreph.com unit. I'm now waiting for the slow boat from China to arrive. ( ) I will update this thread with a how-to, once I get my unit and try it.

The link to the unit I ordered is here: Mazda i-Stop Disabler Kit – Mikstore Car Accessories (mikstoreph.com). I also found similar units available for ~$10 cheaper from AliExpress, but those only mention compatibility with the CX-30. I believe the CX-30 and CX-50 switch boxes are the same but didn't want to risk it.

I find it really interesting that they added the 'compute' complexity for this in exchange for reduced wiring complexity. Hmm. I would strongly doubt they use the resistor ladder method now, even internally. Probably just direct connections from each switch to the MCU.

Anyway, these are pics I took of my pulled (and opened) box, FYI:

 

[Trickster]

I just push the button.🤣

 

[Sparky915]

I was going to get the mikstoreph unit, too, but I don't want my hazard lights to flashing every time I open a door while the car is running. Don't know why they did this. Ruined an otherwise good product.

 

[Trickster]

Interesting thing I discovered a few days ago and did not know existed with the i-stop feature is that the pressure on the brake pedal interacts with the shut off. So if you don’t exert too much pressure when stopped it does not shut off. So that’s kind of a nice touch.

 

[ZeekZirconPPT]

Interesting thing I discovered a few days ago and did not know existed with the i-stop feature is that the pressure on the brake pedal interacts with the shut off. So if you don’t exert too much pressure when stopped it does not shut off. So that’s kind of a nice touch.

That is the human centric part of Mazda. Pretty neat!

 

[RedBaron]

I was going to get the mikstoreph unit, too, but I don't want my hazard lights to flashing every time I open a door while the car is running. Don't know why they did this. Ruined an otherwise good product.

Where did you see that it did this?

 

[Sparky915]

Where did you see that it did this?

 

[RedBaron]

Hmph! Dammit

 

[ChrisP]

This whole discussion is curious to me. I like the way they have it. If you want i-Stop to engage press the pedal harder. If not just drive normally and the car will not engage i-Stop. In 5k miles mine has engaged less than maybe ten times with probably half of those being on purpose - for a period of time I had my doubts as to whether the system was functioning properly.

 

[RedBaron]

This whole discussion is curious to me. I like the way they have it. If you want i-Stop to engage press the pedal harder. If not just drive normally and the car will not engage i-Stop. In 5k miles mine has engaged less than maybe ten times with probably half of those being on purpose - for a period of time I had my doubts as to whether the system was functioning properly.

You may like it, I do not. I like to use the auto hold function at lights/intersections. To use that you also have to press the brake pedal harder which then also engages iStop. Pain in the arse.

 

[ChrisP]

You may like it, I do not. I like to use the auto hold function at lights/intersections. To use that you also have to press the brake pedal harder which then also engages iStop. Pain in the arse.

I've never used the auto hold function. Thanks for pointing it out.

 

[Sparky915]

This whole discussion is curious to me. I like the way they have it. If you want i-Stop to engage press the pedal harder. If not just drive normally and the car will not engage i-Stop. In 5k miles mine has engaged less than maybe ten times with probably half of those being on purpose - for a period of time I had my doubts as to whether the system was functioning properly.

Yeah, but then you have to make a conscious effort to do so. Takes more effort than I care to exert. I like to relax at the stop lights, not think about how hard I'm pushing the pedal. I've gotten into the habit of turning i-Stop off every time I get into the car. Well, 99% of the time, anyways.

 

[ChrisP]

Yeah, but then you have to make a conscious effort to do so. Takes more effort than I care to exert. I like to relax at the stop lights, not think about how hard I'm pushing the pedal. I've gotten into the habit of turning i-Stop off every time I get into the car. Well, 99% of the time, anyways.

we’re of the same mindset. I don’t put any thought to it. I’m just doing what comes naturally.

I guess I don’t push pedal as hard as you do while I’m sitting a light. To me, pushing harder than I want to is work.

 

[RedBaron]

As I said above, I ordered a unit from mikstoreph.com. It took 4 weeks to arrive (from China), but for 2 of those it was held up at the warehouse. When I bitched, they apologized and it started moving the next day and took just another 2 weeks to arrive. The unit does not look like the picture on their website, but just like the ones on AliExpress for the CX-30. It's also marked on the box for the CX-30 too (nothing about CX-50) so if I was doing this again, I'd get a cheaper CX-30 one off AliExpress.

Anyway, installation is easy and it works well. Better still the hazards DO NOT FLASH when the door is open (ignition on or off) unlike the comments above and the note on the web page. I assume they changed the firmware, or that note was for a different variant. Happy about that.

What you get in the box (although the yellow pry tool is totally unnecessary):

There are no instructions with it, but again, installation was very easy. First you need to pull off the driver air vent unit. Just get 8 fingertips (4 shown here as I was taking the photo ) into the side join where the leather wraps back inside the dash, and PULL. The vent and surround will unclip:

Then pull at the inside top of the lower dash and unclip the top clips and pull back enough to get access (you will NOT remove the whole unit here, just bend it back a little). You should see the top white connector into the button box:

Now get your fingernail in to press-in the connector 'catch' on the steering-wheel side of the plug (arrow) and pull the plug out. You may find getting the catch pushed in is a little fiddly, but persevere:

Then plug the cable into the socket on the pigtail from the istop disable unit, and the pigtail plug-end back into the button box:

Then you can peel off the backing of the sticky tape and stick the box against a flat area inside the dash to stop it rattling around (no pic). Push everything back together and you're done!

For those interested, I opened up the unit before I installed it (of course!) and the internals are reasonably complex, including an STC microcontroller, voltage converter and a couple of (what I assume are) driver chips. It obviously does have firmware to communicate over the CANBUS LAN. So, yes, a no-brainer to go buy the unit rather than 'roll your own' as I was originally tempted to do before I found out better!

To have this installed is SUCH a relief for me, as it was really biting my crank when I forgot to turn off iStop and the car turned off on me. YMMV.

NOTE: This is a how-to thread, NOT a discussion on pros & cons of iStop, or whether you personally want or don't want such a device. So please take those comments off to another thread. Thank you!

 

[Sparky915]

Thanks for sharing your findings. I might order one soon...

 

[Trickster]

NOTE: This is a how-to thread, NOT a discussion on pros & cons of iStop, or whether you personally want or don't want such a device. So please take those comments off to another thread. Thank you!

Yeah I don’t think you are allowed to say that, this is a public forum and that would be censorship.🤔
So let me say this,








Kidding🤣
A big ty for the explanation and pictorial of a remedy to so many members pet peeve.
Well done.

Btw, I am finding not too surprisingly that many parts are shared with the CX 30 mechanically and electrically. So as you mentioned CX 30 istop being compatible is another good find.
Cheers.
👍

 

[RedBaron]

Just an FYI update... I had assumed that the unit just disabled iStop at startup and that if you pressed the iStop button after starting/driving it would re-enable it again. I was wrong. In fact, whenever you try to re-enable it by pressing the button, the unit immediately disables it again! I find this a little strange. I would've hoped it would give you the option to enable again, but it seems not. I guess they have their reasons - maybe some race condition fix?