Fitting Cruise Control...

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Re: Fitting Cruise Control...

Post by qwakers » Thu Aug 10, 2017 5:16 pm

just for future reference, no it isnt.... having reread the as data mod thread it is mentioned it should be green/yellow. the one to the left of the one i marked. the original pics being missing certainly makes life hard :)

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Re: Fitting Cruise Control...

Post by SeeJay » Thu Aug 10, 2017 6:37 pm

Yes indeed,well done,mate :thumleft:

But here's an irony..I have an R3 with cruise control as standard...and never use it :roll:
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Re: Fitting Cruise Control...

Post by JamieM » Sun Aug 13, 2017 11:54 am

Obligatory victory photo :lol:
IMG_20170813_112634862.jpg
Was all great until I hit some B-roads, gave it some abuse, then my jumper wire fell out lol :lol:

Now need to find the right wire to sort out something more permanent!
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Re: Fitting Cruise Control...

Post by JamieM » Sun Aug 13, 2017 8:59 pm

Ok, so I located the correct R/G (red with green tracer) wire inside the car thanks to joney. I wanted to avoid modifying the engine bay wiring if possible, so wanted to find the corresponding wire in the cabin to splice into. It's in a connector under the dash on the passenger side, between the blower motor and outside (passenger) wall of the car, in possibly the most awkward place to get to imaginable. I removed the glove box and pulled off the fuse box trim to make getting to it "easier":
InkedIMG_20170813_131316932_LI.jpg
Bingo:

IMG_20170813_131332410.jpg
This is connector "X-07". You can also just about see it without removing any trim if you lie down with your head in the passenger foot-well, shoved right back into the corner and look up to your right with a torch.

IMG_20170813_131409734.jpg
That's the wire! Pictured along with a black jumper wire I stuck in there, to test with a multimeter that it is actually the one that ends up at pin 4P at the ECU in the engine bay (it is). There was no corresponding wire coming out of the other half of the connector, so this is where its path ends in my car. Once I'd confirmed this I added a wire tap:

IMG_20170813_152447465.jpg
...which was probably the single most awkward wire tap I've ever tried to fit ever, due to the location and lack of space for hands. I ended up pulling the fuse box holders and several harnesses out just to make more room:

IMG_20170813_152611606.jpg
Next I just needed to find a suitable ground. Luckily, there was one right next to it. Along with loads of suitable screws. I chose a screw without any grounds already attached to it so I didn't have to bother disconnecting the battery, but it doesn't matter which one you chose:

IMG_20170813_154752377.jpg
I put some spade connectors inline for easier installation / future modification.

Which turned out to be a good call, as although when I put it all back together and went for a drive cruise worked perfectly for a while, unfortunately mid way through my test drive it stopped letting me set a speed after a while. No CEL or anything, but when I scanned the codes I found a hidden DTC "P0571" - Speed control brake switch circuit failure - brake switch A circuit. Even with my now more solid wiring.

Turns out my jumper wire hadn't come loose as I suspected, what had actually happened is what I had feared - the car had detected that the cruise brake switch was permanently grounded and triggered the DTC, which stops cruise from being able to set a speed. The code is stored internally and silently stops cruise working, presumably a safety thing using the two brake switch inputs for redundancy. You can clear the code, and cruise will work again for a short while, but after 5 or 6 brake pedal presses (a short drive...), it will detect that the 2 brake signals don't match, and the code will re-appear and stop cruise from working again. Seems the ECU is too clever :lol:

So it looks like anyone with the 2-pin brake switch such as myself is going to have to do this properly, or else be constantly clearing codes mid drive. Not content with that, I ordered a 4-pin brake switch from ebay, they seem to range from around £18-£21. To make it easier, the 2 pin ones seem to be black with a white connector on the end, whereas the 4-pin ones are all black. I bought this one: http://www.ebay.co.uk/itm/401213715915

Good thing I put those spade connectors in, eh? ;) When my new switch arrives, I'll have to remove the ground, run a new wire over to my new brake switch and plug it into the male spade that goes to the wire tap. Hopefully it will work permanently then! [-o<

--------
EDIT:

Yep, all works now with the 4-pin switch installed and wired in properly, no more DTCs! The first 5 photos of this post are still relevant though - just don't plug in a ground like the 6th final photo - this will eventually also trigger DTC 0703, and give you a CEL. So if you have a 2-pin brake switch grab a 4-pin one off ebay/Mazda and install it like this: viewtopic.php?f=30&t=7129&p=1109088#p1109088. Then connect the new wire to the wire tap we installed in this post and you're golden :thumright:
Last edited by JamieM on Thu Aug 31, 2017 10:13 am, edited 8 times in total.
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Re: Fitting Cruise Control...

Post by binghamf6 » Sun Aug 13, 2017 9:12 pm

Today I've have wired up the 4 pin brake light switch and have run the two wires to the ecu for brake switch and the cc switches and run the rx8cc.2.0 but goes though but does not work.
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Re: Fitting Cruise Control...

Post by JamieM » Sun Aug 13, 2017 9:21 pm

binghamf6 wrote:Today I've have wired up the 4 pin brake light switch and have run the two wires to the ecu for brake switch and the cc switches and run the rx8cc.2.0 but goes though but does not work.
What doesn't work? Can you be more descriptive? Is everything else still working normally? Do you get the orange cruise main light but can't set a speed and get the green light? Or nothing at all? If the latter - maybe double check your wiring? :-k
Last edited by JamieM on Sun Aug 13, 2017 9:23 pm, edited 1 time in total.
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  • '55 Brilliant Black 231
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Re: Fitting Cruise Control...

Post by joney » Sun Aug 13, 2017 9:22 pm

Well that's a pita Jamie. I've think I've pin pointed why it's not working for me to my brake switch so going to have to order a new one :(
If its not broke I'm sure I can find a reason to take it apart :thumright:
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Re: Fitting Cruise Control...

Post by binghamf6 » Sun Aug 13, 2017 9:27 pm

JamieM wrote:
binghamf6 wrote:Today I've have wired up the 4 pin brake light switch and have run the two wires to the ecu for brake switch and the cc switches and run the rx8cc.2.0 but goes though but does not work.
What doesn't work? Can you be more descriptive? Is everything else still working normally? Do you get the orange cruise main light but can't set a speed and get the green light? Or nothing at all? If the latter - maybe double check your wiring? :-k
I get no lights but my car is a 192 if that make a difference I'm pretty sure I've got the wires in the right places as I had to go to the ecu as the wiring is notg there in the loom.

also fitted a new 4pin brake switch.
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Re: Fitting Cruise Control...

Post by JamieM » Sun Aug 13, 2017 10:23 pm

binghamf6 wrote:my car is a 192 if that make a difference
To be completely honest, I have no idea. I don't think it makes a difference, as I'm sure I've read that people successfully got it working on the 192 in the past (in the early days before the PCM patch), by running the extra wires. But then why didn't these guys run into the brake switch issue? :-k I guess the software was different back then, who knows what else the patch changed.

Rx8cc looks like it has run successfully though from your screenshot, and as you don't have a CEL I'm inclined to believe it worked. Something else must be up - I don't know what else to suggest other than checking for faulty wiring/switches etc. (it's possible one of the other switches required for cruise control may have gone bad or is different on the 192? E.g. clutch switch, neutral position switch on gearbox, etc)
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Re: Fitting Cruise Control...

Post by zippyonline » Mon Aug 28, 2017 9:15 am

Before I order myself a new brake switch...what do those with some experience think.

I know I could just pull the plug of the end and look - but the seat is in fully forward position at the moment so I can't actually get in to unplug it - and it's under a car cover with a battery elsewhere - etc.

I have four wires, which is good, so worst case = new switch required. I also know the ones with the white end aren't known for having 4 pins - but this says on the side of it "PBT CSI 4" and the "GJ6A" which is all good. :-k
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Re: Fitting Cruise Control...

Post by zippyonline » Mon Aug 28, 2017 9:17 am

I suspect I'll have unplugged it before the day is out anyways.. :lol:
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Re: Fitting Cruise Control...

Post by JamieM » Mon Aug 28, 2017 11:16 am

My bet is on 2 pin but it'll be interesting if it's not ;)
Author of rx8cc (cruise control mod)
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  • '55 Brilliant Black 231
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Re: Fitting Cruise Control...

Post by zippyonline » Mon Aug 28, 2017 2:35 pm

Oh, I thought I edited my response. It's the wrong part number for 4 pin - it is 2 pin. GJ6E is 4 pin. I'm just off to buy a more useful brake switch. :)

FYI for everyone else, it's only £18 or so brand new from Mazda.
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Re: Fitting Cruise Control...

Post by Sakeiru » Mon Aug 28, 2017 9:40 pm

These colour images should help those who need to add wires to their Cruise Control system. I'll be making a bit of a walkthrough regarding the location of these terminals, and how to add the wires. I've had to do this to my own '8 today and with success. :D
RX8 CC Overview.png
RX8 CC X-05.png
RX8 CC X-06.png
RX8 CC X-07.png
RX8 CC F3-07.png
RX8 CC F3-08.png
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Re: Fitting Cruise Control...

Post by JamieM » Wed Aug 30, 2017 10:49 am

Those colour diagrams are awesome! Where did you get them? And they're for RHD too - the only ones I have access to (via the club shared drive) are B&W, and for LHD cars which have some obvious wiring differences in some areas because of being the wrong way around :lol:

I've now wired up a 4-pin switch properly too. Took some photos so I'll write it up when I get chance. I bought some crimp pin terminals off Amazon which seem to fit in the factory plug - they use standard 2.8mm / 0.11" pins. So you could even stick a few slim female spade connectors in there (the ones they sell in halfords for speaker terminals) and it would probably work, might be tight fit though. I wanted to use the proper factory plug, so examining the pins already in there as best I could without taking them out I bought these, which looked the closest shape I could find:


https://www.amazon.co.uk/gp/product/B01IT43708

They are not completely identical, there is some play and they move around in the factory plug a little, but do click into place in the plug and seem to make contact with the extra pins on the 4-pin brake switch. Simply crimp them onto the end of a couple of wires then insert into the factory plug, use the ones already in there for reference of which way round they go. I then ran one wire to a nearby ground screw, and the other over into the passenger foot well, where I terminated it in another crimp - this time just a standard insulated spade to plug into the connector of the wire I previously tapped into X-07 (and unplugged/removed my ground).

All seems to work reliably now! I did lots of braking on the way to the last monthly meetup in Essex (about an hours drive through spirited B-roads :twisted:), then cruised all the way home on the motorway later when I was tired. All still working, no DTCs :thumright:
Last edited by JamieM on Wed Aug 30, 2017 11:13 pm, edited 1 time in total.
Author of rx8cc (cruise control mod)
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  • '55 Brilliant Black 231
    LC Full bridge, D585s, Cobra exhaust, AEM intake, Exedy stage 1 clutch & ultralight flywheel, M1144 pads, shortshifter, MS-style skirts, rear spats etc, custom 350W RMS cabin-firing sub build (ski hatch), cruise control (obvs)
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Re: Fitting Cruise Control...

Post by Sakeiru » Wed Aug 30, 2017 9:21 pm

JamieM wrote:
Wed Aug 30, 2017 10:49 am
Those colour diagrams are awesome! Where did you get them? And they're for RHD too - the only ones I have access to (via the club shared drive) are B&W, and for LHD cars which have some obvious wiring differences in some areas because of being the wrong way around :lol:
I just happened to still have access to MESI, which changed on the weekend :lol: My old dealership account finally got suspended after just over a year since leaving. But I got what I needed out of it. :D Good shout on the terminals! They do look pretty similar to the ones I salvaged for mine. :thumright: And I'm glad to hear yours was a success too! Safe to say, this mission is complete! 8)
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Re: Fitting Cruise Control...

Post by JamieM » Thu Aug 31, 2017 12:22 am

As promised, here's some photos of the process of adding the 2 new wires for older cars without the brake switch wiring already in place.

I was in a bit of a rush to get this done in time before my car went off to LC Rotary, so I've only just looked at the photos and realised I hadn't taken as many as I thought, sorry! For the connection to X-07 you'll have to make do with those from my previous post on grounding here. It's the same wire, just rather than being plugged into the ground (which I've now removed) I was talking about in that post, it now plugs into a new wire that I've run from the passenger foot well over to the drivers foot well, via the brake switch to a new ground. Don't have the car now so can't take any more photos of that until I get it back! Basically use the first 5 photos of that post, ignore the last (6th) one.

As I mentioned in my last post above, I bought some 2.8mm crimp receptacle terminals to do the job of wiring in the brake switch properly.

These can be crimped onto the end of a wire:
IMG_20170823_183943718.jpg
Then inserted into the factory brake switch plug like so:
IMG_20170823_185043739.jpg
Pay close attention to the orientation of the existing terminals in the plug to make sure you get them the right way around, they will 'click' into place when inserted correctly. You could instead use normal slim spade connectors and do away with the factory plug, or solder directly to your new 4-pin brake switch terminals, but that's not a very nice solution ;)

Make sure you use a wire that's long enough - don't forget one of them has to make it's way all the way over to the passenger foot well to the other side of the glove box to X-07. The other has to reach a ground wherever is convenient.

Removing the old brake switch is easy, just unplug it then twist and it will pop out. The direction to twist I forget but it is obvious if you get your head under there and look at which way the holes line up. Insert the new switch in the holes and twist in the opposite direction until it locks into place.
IMG_20170823_185055549.jpg
With the 2 new wires crimped and inserted into the factory plug, you can then plug the new switch in. I threaded both the new wires through the loose plastic sleeve you can see in the photo above and cable tied them up out of the way of the pedals:
IMG_20170823_202804074.jpg
Rather confusingly, I used a blue/white wire for the ground connection and a black wire which you can barely see for the connection to the ECU via X-07 (because it was the only wire I had lying around that was long enough :P). They both head in opposite directions. The blue wire I crimped a ring terminal onto the other end and then bolted to a convenient ground under the dash on the steering column:
IMG_20170823_202754006.jpg
The black wire goes up and over the steering column, then I threaded it through underneath the stereo. If you remove the gear stick and surrounding plastic trim, you can take out the ash tray which gives you access to pull the wire through without removing the stereo (sorry there's no photos of this bit - I forgot!). The process is almost identical to installing the extra wire for the steering wheel cruise buttons (in fact it would be convenient to do them both at the same time...)

I then threaded it from there through to the passenger foot well, looping it around existing looms and cable tying as necessary, until it gets to the spade connector I left attached to my wire tap of the Red/Green wire in connector X-07. I crimped another spade connector onto the end of the new wire, unplugged/removed the old ground, plugged in the new wire and then put everything back together. Job done :thumleft:

Location of the connector X-07 and the Red/Green wire to tap: viewtopic.php?f=30&t=7129&p=1106175#p1106167
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  • '55 Brilliant Black 231
    LC Full bridge, D585s, Cobra exhaust, AEM intake, Exedy stage 1 clutch & ultralight flywheel, M1144 pads, shortshifter, MS-style skirts, rear spats etc, custom 350W RMS cabin-firing sub build (ski hatch), cruise control (obvs)
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Re: Fitting Cruise Control...

Post by Juey » Wed Mar 28, 2018 6:16 pm

Regards my cruise speed limiter....
JamieM wrote:
Mon Jul 24, 2017 10:07 am
Quite possibly, but you'd have to figure out which bit of the as-built data corresponds to the speed (it might be 100 or 62 stored in hex - perhaps 0x64 or 0x3E but it may be encoded differently). We currently don't know this - but if someone figures it out it should be fairly easy to change it for you using exactly the same method :) (assuming it is stored in the as-built data and not enforced in a different way)
Where would I find the information or 'hex' as you call it?
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Re: Fitting Cruise Control...

Post by JamieM » Wed Mar 28, 2018 9:28 pm

Hex = Hexadecimal, just an alternative system for representing numbers, often used in computer systems for convenience. I was simply guessing that you might be looking for either the number 62 (mph) or 100 (kph), which when represented in hexadecimal are 0x64 and 0x3E respectively. I.e. if you were looking through some code/data for them, you'd probably look for "64" or "3E" or "3e" rather than the actual decimal numbers themselves (again, a guess - they could be encoded completely differently - but it'd be a good starting point). I don't know where you'd look though - I myself haven't found any such bytes in the as-built data, or anything looking along the right lines, which leads me to believe it's stored somewhere else, unfortunately (the ROM maybe?). Unless it's encoded differently.

Hexadecimal explanation, for those that don't know: Normal decimal numbers are base 10, i.e. you count up from 0 to 9 then add a 1 to the "tens" column to get 10 which means "one ten, zero units", 11 means "one ten plus one", etc. Hexadecimal numbers are base 16, so there isn't a "tens" column but rather a "sixteens" column instead. Since we don't have single digits to represent the decimal numbers ten to fifteen, the letters 'A' to 'F' are used. A means ten, B means eleven, etc up to F means fifteen. So counting sequentially in hexadecimal would look like this: 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F,10,11,12,13,14,15,16,17,18,19,1A,1B,1C,1D,1E,1F,20,21, etc. The prefix "0x" is usually added to numbers written in hexadecimal, in order to avoid confusion with ordinary decimal numbers. E.g. 0x3E mean "three sixteens and fourteen units" i.e. (3 x 16) + 14 = 62 in decimal. So with 2 digits, decimal numbers go from 0 to 99, but hexadecimal numbers can go from 0x0 to 0xFF, which is equivalent to 0 to 255 in decimal (F represents fifteen, so 0xFF is "fifteen sixteens plus fifteen"). This is why they are often used in computer systems, since a two digit hex number can conveniently represent exactly 1 byte of data, i.e. 8 bits = 2^8 = 256 different states (zero is counted as a state so there's 256 states even though the biggest 2-digit hex number is 255).

Anyway, based on a 3-4 post conversation I had over here with an owner of another similar era Mazda car, I think I may have actually been wrong (not the first time haha :P ), and the JDM ROM is actually different code, rather than just having bits of it disabled by the as-built data, and the speed limiter is baked into the ROM along with the other differences. Also supported by the fact that JDM cars have different maps / behaviour in other departments / reject non-OEM coils etc too. In which case, assuming you don't want to change to a different ROM from EU/US/AU, the JDM limiter wouldn't be able to be changed in the as-built data - you'd have to edit the ROM. Dunno if MazdaEdit can do anything like this? I have no idea, sorry :-k
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Re: Fitting Cruise Control...

Post by Juey » Thu Mar 29, 2018 4:14 pm

Fair enough, looks to be very tricky and risky indeed.

Still useful for avg speed cameras at 40, 50, 60, just not high speed cruising.
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Re: Fitting Cruise Control...

Post by Kellytm272 » Fri Mar 30, 2018 9:54 pm

Just to say thanks to Jamie, got cruise working a treat. Very simple. The usb to obd I bought is shown below
569E0BC7-2CCB-49F1-B906-ECC27A547028.jpeg

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Re: Fitting Cruise Control...

Post by obakemono » Fri May 04, 2018 12:22 am

Kellytm272 wrote:
Fri Mar 30, 2018 9:54 pm
Just to say thanks to Jamie, got cruise working a treat. Very simple. The usb to obd I bought is shown below
569E0BC7-2CCB-49F1-B906-ECC27A547028.jpeg
Similar to the one I have, without the switch which I'm going to add, really struggling to get the drivers working though. Going to try my old windows xp laptop next
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Re: Fitting Cruise Control...

Post by Kellytm272 » Fri May 04, 2018 12:41 am

I used it on a windows 10 machine, don’t recall having to install drivers though.

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Fitting Cruise Control...

Post by Pensive » Sun Jun 24, 2018 11:24 am

So I have 4 wires, but a white plug. I haven’t disconnected it because the Mazda advice is to get a new plug after disconnection.

Does a white plug in a black socket mean I’m missing the 2 extra pins despite having the 4 cables going in? I have to unplug it to find out I guess...

Does it damage the plug when you disconnect? Or is that scaremongering?

Think I need to order the black plug regardless....can anyone confirm?

It’s a GJ6A so almost certainly 2 pin I think....can clearly see 4 wires going in though.

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Re: Fitting Cruise Control...

Post by zippyonline » Sun Jun 24, 2018 12:45 pm

Pensive wrote:
Sun Jun 24, 2018 11:24 am
Does a white plug in a black socket mean I’m missing the 2 extra pins despite having the 4 cables going in? I have to unplug it to find out I guess...

Does it damage the plug when you disconnect? Or is that scaremongering?

Think I need to order the black plug regardless....can anyone confirm?

It’s a GJ6A so almost certainly 2 pin I think....can clearly see 4 wires going in though.
Yes exactly what you think - exactly the same situation as me. Unplugging it and plugging it back in made no difference to anything for me.

See these quotes: :)
zippyonline wrote:
Mon Aug 28, 2017 9:15 am
Before I order myself a new brake switch...what do those with some experience think.

I know I could just pull the plug of the end and look - but the seat is in fully forward position at the moment so I can't actually get in to unplug it - and it's under a car cover with a battery elsewhere - etc.

I have four wires, which is good, so worst case = new switch required. I also know the ones with the white end aren't known for having 4 pins - but this says on the side of it "PBT CSI 4" and the "GJ6A" which is all good. :-k
zippyonline wrote:
Mon Aug 28, 2017 2:35 pm
Oh, I thought I edited my response. It's the wrong part number for 4 pin - it is 2 pin. GJ6E is 4 pin. I'm just off to buy a more useful brake switch. :)

FYI for everyone else, it's only £18 or so brand new from Mazda.
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