Taping into vehicle speed pulse

[AhmedBahgat]

Hello mates

My car is Mazda 3 MPS which is the Australian version of the Mazdaspeed3, my car is Gen 1 2007, I am trying to find the pulse speed signal in the back of the instrument panel, can you help me please identifying it

Cheers

[thatguy0o0]

Not sure exactly what you are looking for but if it is speed sense or tach all that stuff is probably going to be digital through data bus/can high low by the time it gets to the instrument cluster. You can grab tach at the ignition coil or fuel injector and speed sense is through the wheel speed sensor. I know this isn’t much help but maybe it’ll point you in the right direction?

[AhmedBahgat]

Originally Posted by thatguy0o0 Not sure exactly what you are looking for but if it is speed sense or tach all that stuff is probably going to be digital through data bus/can high low by the time it gets to the instrument cluster. You can grab tach at the ignition coil or fuel injector and speed sense is through the wheel speed sensor. I know this isn’t much help but maybe it’ll point you in the right direction?

Thanks mate for the reply

I am trying to feed a frequency switch/relay with the speed pulse where at a specfic frequecy the relay will latch

I think you are right, as I could not find anything through the instrument panel, seems the speed is calculated by the abs module and passed to the ecu via can bus

I am thinking to tap into any of the rear wheel speed sensors, would that be ok?

cheers

[thatguy0o0]

Originally Posted by AhmedBahgat Thanks mate for the reply I am trying to feed a frequency switch/relay with the speed pulse where at a specfic frequecy the relay will latch I think you are right, as I could not find anything through the instrument panel, seems the speed is calculated by the abs module and passed to the ecu via can bus I am thinking to tap into any of the rear wheel speed sensors, would that be ok? cheers

Can't say because I have never done it. I would bust out a multimeter and see what kind of signal you are getting at the sensor. If you are just using it to switch a relay it shouldn't be too much of a draw I wouldn't think.

[AhmedBahgat]

Originally Posted by thatguy0o0 Can't say because I have never done it. I would bust out a multimeter and see what kind of signal you are getting at the sensor. If you are just using it to switch a relay it shouldn't be too much of a draw I wouldn't think.

Do you think i should use a diode to stop the signal going back over the tapping wire and distrubs the original sensor signal?


Cheers

[AhmedBahgat]

Gents, this is way too complicated and I will ba taking the risk to damage either the instrument cluster or the ABS module, so I ended up buying a can bus interface that will expose the VSS and RPM via two wires, awesome product but very expensive, it costs 180 oz dollars

[Spectrix]

What are you switching with the VSS?

[Jeff23spl]

Originally Posted by Spectrix What are you switching with the VSS?

I'm curious also....

i would not tap into any sensor without an isolator. i installed a high feature w/m controller on my 2007 that was looking for RPM signal pulses. I taped into #1 coil trigger signal. IT worked 10sec and then the coil smoked with a blown fuse...Fortunately ECM wasn't hurt...
I bet the controller was adding a capacitive load into the circuit that overloaded the coil or something like that.....
I just installed an isolator that i made myself with a transistor in between and hourra!

https://i.stack.imgur.com/INUEl.png


ABS sensors are just a proximity sensor giving a similar signal but taping into it may affect the abs controler the same way (or may not but i wouldn't take the risk...)

The other option may be to fit a second abs sensor into the hub by drilling a second hole etc and keep that one only for the added device......but i didn't look at it to confirm it is something possible. i just say it as a feed for tough....

[Jeff23spl]

you can use this maybe
CAN Bus Speed Pulse Interface | CANNECT PULSE

[AhmedBahgat]

Originally Posted by Jeff23spl you can use this maybe CAN Bus Speed Pulse Interface | CANNECT PULSE

That is more expensive than the one the bought and it only exposes the vss, the one i bought made in the uk and exposes vss and rpm

Cheers

Originally Posted by Jeff23spl I'm curious also.... i would not tap into any sensor without an isolator. i installed a high feature w/m controller on my 2007 that was looking for RPM signal pulses. I taped into #1 coil trigger signal. IT worked 10sec and then the coil smoked with a blown fuse...Fortunately ECM wasn't hurt... I bet the controller was adding a capacitive load into the circuit that overloaded the coil or something like that..... I just installed an isolator that i made myself with a transistor in between and hourra! https://i.stack.imgur.com/INUEl.png ABS sensors are just a proximity sensor giving a similar signal but taping into it may affect the abs controler the same way (or may not but i wouldn't take the risk...) The other option may be to fit a second abs sensor into the hub by drilling a second hole etc and keep that one only for the added device......but i didn't look at it to confirm it is something possible. i just say it as a feed for tough....

You are right mate, that is why I wll not tap into anyting other than the can bus

Cheers

What I am trying to do guys is simply, not that simple, to lock the doors when the car reaches 20 km/h, and if i drop a passenger and frive again the passenger door should lock again when the car reaches 20 km/h

Cheers

[Spectrix]

Originally Posted by AhmedBahgat What I am trying to do guys is simply, not that simple, to lock the doors when the car reaches 20 km/h, and if i drop a passenger and frive again the passenger door should lock again when the car reaches 20 km/h Cheers

Thanks, that's a very useful feature. If you would be as good as to share your work with us after you've finished, it would be much appreciated.

[AhmedBahgat]

Originally Posted by Jeff23spl They have models that give 2-3-6- or even 15 signals including some about door latches too...For the price i didn't compared to value of the 2 different money type...

Yes mate, the price goes up by the number of data you want it exposed from the can bus, it can be up to 400 bucks

Cheers

Originally Posted by Jeff23spl funny, there is probably some dangerous place where it could be usefull but were i live, we don't lock the doors most of the time.... Many american car have this built in feature and i really hate it because i don't find use for it. Now it is probably better with remote sensing of the keys but back in time there was some that could lock the door after xxx sec being in reverse or drive. Meaning if you just move the car few feets, get out quick and close the door, it would lock by itself with the car running and the key on the steering column....We used to have a focus at work and we had 2-3 spare key because it happened all the time...

If you have been exposed to a car jack attempt, then you will diffenitly apprecite such feature

As for the car locking itself and locking you out whle running, it will be impossible to happen because the car cannot drive by itself and reachs 20 km/h to lock the doors, I can however change the threshold and make it locks the doors at higher speeds

I believe the autmatic door power locks is one of the most usefull features for cars in the 21 centuries

Cheers

Originally Posted by Spectrix Thanks, that's a very useful feature. If you' would be as good as to share your work with us after you've finished, it would be much appreciated.

Yes Spectrix, I wll certainly share the infor in great details, I am still waiting for a time delay switch as all I need is momentary negative for under a second to lock the doors or unlock them, I will keep you informed

Cheers

There are lots of bugs when I quote to reply, the forum messes the posts completely, please fix

Cheers

[Spectrix]

Originally Posted by AhmedBahgat If you have been exposed to a car jack attempt, then you will diffenitly apprecite such feature

This is the reason I desire the feature. In my case, driving through shady areas in the middle of the night coming home from work. I seldom remember to lock the doors manually.

Originally Posted by AhmedBahgat There are lots of bugs when I quote to reply, the forum messes the posts completely, please fix Cheers

You're doing okay, once you get used to the vBulletin codes (square brackets, commands and forward slash characters) you'll be able to quote and post successfully (as you have above, perhaps after multiple attempts?)

It's certainly more difficult quoting multiple parties.

[Jeff23spl]

Originally Posted by AhmedBahgat That is more expensive than the one the bought and it only exposes the vss, the one i bought made in the uk and exposes vss and rpm Cheers

They have models that give 2-3-6- or even 15 signals including some about door latches too...For the price i didn't compared to value of the 2 different money type...

[Jeff23spl]

funny, there is probably some dangerous place where it could be usefull but were i live, we don't lock the doors most of the time....

Many american car have this built in feature and i really hate it because i don't find use for it. Now it is probably better with remote sensing of the keys but back in time there was some that could lock the door after xxx sec being in reverse or drive. Meaning if you just move the car few feets, get out quick and close the door, it would lock by itself with the car running and the key on the steering column....We used to have a focus at work and we had 2-3 spare key because it happened all the time...

[lazza151]

Luckily I drink a lot of coffee , so remembering to push the button has not been a problem.

That said, I have been to lazy to read the owners manual to activate the auto lock function .

[AhmedBahgat]

I wish I am like you mate, but I don't drink coffee or tea, haha

I am still working hard on it, a bit complicated especially all oz mazda 3 don't have the lock/unlock wire for which you lock by supplying 1000 ohms ground and to unlock by supplying ground to that lock/unlock wire

I went to the wreckers today and checked 10 mazdas from 2004 till 2008, none has the lock/unlock wire in the drive kick panel nor the blue/black wire in j-06 pin T in BCM, pin T in plug j-06 is empty in all oz mazdas 3, however the oppsite pin is in the BCM so I bought another j-06 from the wreckers for 3 bucks and managed to dismantle it and remove the wires and their pins from it and now I can insert that lock/unlock wire in j-06 and hoping the BCM will respond to it when I supply the lock/unlock signals

Cheers

[lazza151]

Well good luck with the wiring fix.. I almost always have to pay someone to sort electrical or mechanical issues out.

Only things i have done myself are cleaning the BOV and installing the oil flow restriction bolt for the smoking turbo...

[AhmedBahgat]

Originally Posted by lazza151 Well good luck with the wiring fix.. I almost always have to pay someone to sort electrical or mechanical issues out. Only things i have done myself are cleaning the BOV and installing the oil flow restriction bolt for the smoking turbo...

I do eveything to my car since brand new, I only used mazda service for the first two services 12 years ago and said no way I will let them touch my car again

If i am successful in doing what i want to achieve with the power lock, I will make a video about it on my youtube channel and you will have a chance to see how I kept my car immaculate for all those years, the biggest jobs I did to my car


Changing the VVT
Changing the cartridge oil filter housing to the spin-on type one
Whiteline swaybars

Cheers

[AhmedBahgat]

Hello all

Sorry for the delay, I was waiting for the final piece of the puzzle to arrive from China, I got it yesterday and took today off to finish the system that I have thought will do the job for me, it is a bit complicated but with clear and detailed instructions of how I did it, it may be easier to comprehend than what I am thinking, the best way to show this would be a video, in this video I will explain the following

1- The objective of the project
2- The difficulties I have faced and how I got around them
3- The installation for which I did my best to make it as plug and play as possible
4- The cost

All my videos about my Mazda 3 MPS Gen 1 on my channel are in Arabic as I was trying to educate the Arabic community about this car, there is more than enough English videos about this car, however I will make an English version for this video just for you guys, especially that I found very little and conflicting information about the Mazda 3 2006 Lock/Unlock system, and I am sure some of you may find important information in it, and possibly others may copy my solution which will surely work for different Mazdas and possibly for different cars all together

Talk to you soon

Cheers

[AhmedBahgat]

Hello all

Sorry for the delay, been flat out and still, this is the final design I came up with and it works exactly as German cars, I have a Golf R 2018 and an Audi 1.8T 2015, both have the auto power lock system @ 20 km/h, so I studied how they work and came up with a design for my Mazda that works exactly like them, I will explain every part of the harness in the video when I record it pretty soon

Cheers