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Discussion Starter · #1 · (Edited)
ECU pinouts, Schematics.'94/5 MX6 / PGT - OBDI and 95/6 & 97/8 Millenia / Eunos OBDII

OK... I have done a TONNE of research and I am now in a position to share my findings. (also posted on probetalk.com)

This has taken WEEKS if not MONTHS to workout, and I am looking for feedback on the accuracy, please. (I will continue working on it)

Basically it is a VERY comprehensive doc (PDF) with all the ECU Diagrams, ECU schematics, ECU pinouts, colours, mappings etc for
the;
- MX6 / PGT OBDI (1994/5)
- Millenia / Eunos 800 - ODBII - 1995/6/7/8 (KLK1 style ECU .. maybe the KLK7 also)
- Millenia / Eunos 800 - ODBII - 1997/6/7/8 (KLP2 style ECU ... has a different connector to the K1K1 & KLK7 ECUs)

I got so frustrated with the lack of information for a Millenia/Eunos/Xedos ECU and swap (mapping the ECU wiring) especially for a KLK7 ECU that I acquired from a 1997 Eunos 800 (in Australia)... that I put this together..

*EDIT (22nd Sep 2018): I discovered that the KL68 ECU, is for a MANUAL Xedos (Eunos). Apparently the Xedos was released as a manual in Europe. Why is this important? Well, no more error codes related to the ECU's that were originally meant for ATX versions like the KLK7, in a MTX mx6. So the best budget ECU for this swap for mx6's with MTX will be the KL68*

[updated link 28 Apr 2018]
https://drive.google.com/open?id=1NWrukTk7aGrqQRRZl5JHtp00WXdMDwLo

Breakout adapter - 64 pin
https://drive.google.com/open?id=1vCwkcFba_dyfQZZKnrvN5d__4gNncJVp

Breakout adapter -76 pin
https://drive.google.com/open?id=1wW4uAtIQ35ru5xl8ALnah0cypCINS6oJ
 
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Discussion Starter · #2 ·
It is for the ... V6 2.5L KLDE/ZE engine.

If you are considering the Millenia/Eunos 2.5L (OBDII) ECU swap you WILL also need the Mass Air Flow [MAF] Assembly (KL47), Intake Air Temperature Sensor, and optionally the Throttle Body (KL47) modified for the also optional KLG4 intake manifold.

Most people select the KLP2 ECU (2000), but I have a KLK7 ECU from a 1997 Eunos 800. From what I can tell the KLK1 ECU is JDM and has the same connector as the KLK7 ECU... I am making the assumption that Mazda have not changed the wiring between the JDM (KLK1) and Australian (KLK7) ECUs.

Has anyone who has done this swap put in all four Oxygen Sensors? (2 only for the MX6/PGT ODBI ECU)

Enjoy! :)
 

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Can't believe you've posted this in the last couple of day (it's awesome great job!). Just yesterday I went to Sydney to look for some other parts when I came across a mid 96 model Eunos 800, couldn't believe my luck with it being the na one, I grabbed the ECU, IAT and MAF. Didn't realize I needed needed the throttle body (whats better about it, is it actually required?)

My intention is to stick it all in my 95 626, have you or anyone else installed this KLK7 ECU in an MX6/Probe etc..?

I compared all the wire colours you listed and found a couple discrepancies with my ECU, as pictured:







One more picture to come
 

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Discussion Starter · #5 ·
You're welcome... Merry Christmas!!

The colour codes were based on a **1997 KLK7 Eunos 800 2.5L (I have also) .. so there maybe a few differences with an earlier year (but post 1995), although I think you are right where I put P (pink) it should be W (white) in most cases... I'll check the others. The colours maybe important when looking at the schematic for the different Eunos 1997/97 connector towards the end of this doc. This will hopefully validate some of the pin descriptions.

The pin descriptions are based on the KLK1 ECU (see the URL link below the each table) .. I could not find one for the KLK7, not even from the local Mazda Stealership. I have made the assumption they will be much the same. The KLK1 ECU is the JDM one... btw (see ebay)

The KL47 Throttle body is a bit bigger, and most people hourglass the neck and butterfly the shaft. (and if really keen polish it)

It is a work in progress... really appreciate the corrections!!

Work in progress.. any help gratefully accepted :)
 

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It is for the ... V6 2.5L KLDE/ZE engine.

If you are considering the Millenia/Eunos 2.5L (OBDII) ECU swap you WILL also need the Mass Air Flow [MAF] Assembly (KL47), Intake Air Temperature Sensor, and optionally the Throttle Body (KL47) modified for the also optional KLG4 intake manifold.

Most people select the KLP2 ECU (2000), but I have a KLK7 ECU from a 1997 Eunos 800. From what I can tell the KLK1 ECU is JDM and has the same connector as the KLK7 ECU... I am making the assumption that Mazda have not changed the wiring between the JDM (KLK1) and Australian (KLK7) ECUs.

Has anyone who has done this swap put in all four Oxygen Sensors? (2 only for the MX6/PGT ODBI ECU)

Enjoy! :)
Currently doing the swap with a JDM KLDE and KLK1C ecu in a 2003 protegé5. Will have complete emissions stuff and 4 O2 sensors.

I'm having trouble getting the OBD2 port working. Tried your pinout but for some reason it wont work. Also tried like 30 different configs to no avail. My ecu is marked late 98 (cant remember the exact date). Do you have any input on that??

Also, my ecu doesn't want to ground the protegé fuel pump relay. It actually does but only for a thou of a second. Does the ecu need the exact relay to work correctly?

Thanks for any help you can bring!
 

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After tearing everything down, researching, reading, trial and error, plugging this, unplugging that, I finally found my problem. I will share this so hopefully someone will figure this out before shelling money on a worthless ECU like I did.

Also advice to anyone looking into the KLK1 ecu.

Some KLK1 ecus have immobilizers. You will need the exact immobilizer module and coded key from the car the ecu came from. You cannot use an immobilizer module from another car (please prove me wrong on this, I want to use my ecu!).

My symptoms were I couldn't get the ecu to output the ignition trigger signal. My wiring was from a 96 mx3 GS, adapted to this pinout here, ECU would control the injectors but wouldn't output the ignition trigger signal. Plugged a 96 mx3 GS ecu in (without modifying anything wiring side) and instant injector and ignition control.

There seems to be 2 identifiable KLK1 ecus, KLK1B and KLK1C. Cannot confirm if the B/C letter at the end of the ecu codes relates to immobilizer/non-immobilizer models. I spent many many hours researching all of this, translating russians sites and what not, to no avail.

The easiest solution here would be to buy a KL47 ecu from a USDM 1995 Millenia. Same wiring, ecu pinout, accessories, still uses MAF instead of VAF, 4 O2 sensors, none seems to be immobilizer models so no trouble with that.

I'm in the process of trying to use the K853 ecu as a piggyback to control spark only, so I can keep my MAF and correct fuel tables. No clue if this will work yet, will probably end up scrapping the KLK1 ecu altogether and use the K853 ecu only until I find a KL47.

Some other random facts about the K853/KLK1/KL47 ECU logics that might help someone along the way :

The ECU only outputs ignition trigger signal if crank AND cam (in dist) signals are present at the ecu.

My LAUNCH code reader+ and ELM327 bluetooth dongle wouldn't connect to the KLK1 ecu. I didn't try any more serious diag tools.

When doing the HEI mod, the W tab should connect to the output device ground, in my setup it was the wire next to the ignition trigger signal wire on the dist 6 wire connector. The bolt through ground can be connected to any ground source. If you don't, unwanted noise will be present. This manifested by fooling me into thinking I had a weak ignition trigger signal when using a voltmeter to read voltage on the wire. It showed a changing 0.3V with negative lead to battery negative while cranking. Showed 0.0V when negative lead was put to correct ground. It also gave me a weak spark on initial crank then no spark at all, leading me to think something was wrong somewhere else. Also, what is shown everywhere as ignition - wire on every diagram is pointless, unless you want to use the diag box to diagnose ignition problems. It connects to nothing, Mazda actually deleted this wire on later models. If you have anything over 95, reuse the provided 12V from the dist 3wire plug (biggest wire, no matter the color). Then another wire will be for tach input, with last wire going to diag box only. At one point, Mazda used an ecu provided tach signal so you will only find the 12V coil wire. The KLK1 ecu is setup like this, pin 1T.

I will add info along the way as I feel it.

Also special thanks to OP, your work has been essential to my swap! I can fathom what kind of work went into this and cannot thank you enough.
 

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Also, I forgot that the ecu wouldn't control the fuel pump. I believe this is part of the immobilizer system, cutting fuel at the pump and spark signal from the ecu at the same time.

I think immobilizers are a 98+ thing. Previous ecus shouldn't be (don't blame me if they are). My ecu was stamped 98/10 on the circuit board IIRC so it would have been a 99 model at least. The KLK1B ecu being 95-98 and KLK1C 98+ starts making sense more and more, although only an hypothesis at this point. I've contacted the ebay seller I bought mine from, I'll try to see if he has 98- ecus around though I might be more interested in a KL47 ecu for peace of mind and OBD2 port connectivity with my diag tools.

More as I figure it out.
 

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Discussion Starter · #9 ·
I am so pleased that someone else is taking this to the next level.

I was confident with all the mapping I did, but I too could not communicate with the ECU using an ELM327 tool.

The car would crank, superficially everything looked ok, but the very technical trouble-shooting was something I did not have time to do.

Keep up the great workl!
 

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I am so pleased that someone else is taking this to the next level.

I was confident with all the mapping I did, but I too could not communicate with the ECU using an ELM327 tool.

The car would crank, superficially everything looked ok, but the very technical trouble-shooting was something I did not have time to do.

Keep up the great workl!
I can now confirm your obd2 port mapping as Mazda uses the same mapping on several other models that share the 4 connector Denso ecu layout. I got to check several wiring diagrams and even straight up cars at the scrap yard to confirm this.

I gave up for now on the KLK1C ecu, ordered a KL47 yesterday so I can get my car running before winter.

My engine would crank with the KLK1C ecu also, but the Ecu wouldn't control spark or fuel pump. There are additionnal pins somewhere on the ecu connectors that should be linked to the immobilizer unit. I cannot find anything on the wiring diagrams I have access to, most usdm 96+ Mazda Ecus dropped the Denso Ecus for Mitsubishi units, with completely different connector layouts. I couldn't ever find a KLK1C wiring diagram, except for your pinout. I believe everything is identical to the KL47 layout as of now, so it will be simple enough to swap over. I'll post it here if I encounter discrepancies.

The KLK1C ecu will serve as an expansive paper weight for now... Wish I had bought that KLK1B ecu instead (both of them same price, both available at the time, sprung for the shiny newer one....), might already be driving my car if I did.
 

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Discussion Starter · #11 · (Edited)
Here is my adapter :)
 

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Discussion Starter · #12 · (Edited)
Hi All,

I was looking at how well supported the MX5 was for after market mods, including a PNP ECU called the ME221 ... and then I thought ... with the introduction of ODBII in 1996 and the totally redesign of the ECU pinouts, would the MX6 roughly follow the same pinout redesign as the MX5. :nerd: I Believe the answer is yes!!

As you all are aware, pre-1996 ODBI car wiring to the ECU is COMPLETELY different and therefore incompatible with the later ODBII ECU.

Then I found this;
https://www.flyinmiata.com/support/instructions/ecu/OBD2_rewire.pdf

Also available here;
https://drive.google.com/file/d/0B6eHpIwkKKDAYjBLckg1bVJEQms/view?usp=sharing

From the document (above) and comparing it to my mapping.. I found that pins 4A to 4Z (26 pin connector) all appear the same as those for the MX6 except for 4Y/4Z which are extra fuel injectors #5 and #6 on the MX6 V6.

Much the same for 3A to 3P and 1A to 1V

I have not done the full comparison yet but I have noted a few differences, which may be mistakes on my part .. e.g. in my mapping 3M is the "Knock Sensor" but it is the "fuel injector ground" in the document above.

Looking at column 1 and 4 of the tables (in this doc) it looks very close to that of the ECU pinouts for '99 Millenia/Eunos 800

... stay tuned :grin2:
 

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Discussion Starter · #13 · (Edited)
Hi All,

Any assistance or validation would be appreciated!!:smile2:

Thanks

GQ

Updated mappings (see link below).. I believe I am almost there.. I am having real trouble trying the get the location of the Camshaft position sensor.. I have listed them as;

ODBII........................................................................................................ ODBI
4F Camshaft Position Sensor, SGT signal (marked as not connected on KLK1) .. to C26-23
4G Crankshaft Position sensor SGC (in Distributor)........................................ to C26-24
 

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Discussion Starter · #14 · (Edited)
THIS IS GOLD!!!

I can't believe with over 2,000 views there is not a single comment except for xmaster19!!
I have made a few changes .. including to the OBDII "diagnostic connector" wiring

I am also working on the KLP2 mappings

I am bidding on an MX6 in the UK, a non-runner... which I will use as a project car to make sure the ECU upgrade works.

Yeah!
 

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I dropped the KLK1 ecu altogether. I tried the KL47 ecu in, l could finally communicate with it through my scanner. I'm also confident it will control spark. Didn't have to change any wires from the KLK1 pinout. I'm also hours away from my first start. Thanks again for your work, it definitely helped me through my ecu/wiring head aches.

Here's the wiring diagram from a 95 millenia which matches your KLK1 ecu pinout, if it can be of help to anyone :

http://www.revbase.com/BBBMotor/Wd/DownloadPdf?id=47421
 

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Discussion Starter · #16 · (Edited)
I bought a non-runner, with an "electrical fault", which I have finally fixed and got working. TODAY!!:grin2:

I have learnt a great deal about the crankshaft position sensor in the distributor.. I basically rebuilt the existing distributor to get a spark from the stock ECU Today!!

The distributor has two main parts, the coil (transformer) and the "hall effect" ignition module... basically a bunch of resistors and a few transistors. I bought the ignition module here: SPECTROMATIC LTD: J888 ignition module MAZDA MX-3 <= worked GREAT [It is the same for the MX-6 and MX-3]

To understand more about the common ignition module problem,
check this out...
ErgonITe - Probe/626/MX6 FAQ - Problem Areas

So, the one thing I am unsure of in my mappings is the distributor position sensor (ignition module) pin-outs which sends an earth pulse to the ECU, to tell the ECU when to send a pulse to the coil aka spark, if these are not correct, there will be NO SPARK.

I got your PM xmaster19, tried to PM you back "a long time ago" but you're settings on mx6.com are preventing personal messages (PMs).

Next week I'll have more time to verify the pin-outs.. unless you get there first.. LOL
 

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I bought a non-runner, with an "electrical fault", which I have finally fixed and got working. TODAY!!:grin2:

I have learnt a great deal about the crankshaft position sensor in the distributor.. I basically rebuilt the existing distributor to get a spark from the stock ECU Today!!

The distributor has two main parts, the coil (transformer) and the "hall effect" ignition module... basically a bunch of resistors and a few transistors. I bought the ignition module here: SPECTROMATIC LTD: J888 ignition module MAZDA MX-3 <= worked GREAT [It is the same for the MX-6 and MX-3]

To understand more about the common ignition module problem,
check this out...
ErgonITe - Probe/626/MX6 FAQ - Problem Areas

So, the one thing I am unsure of in my mappings is the distributor position sensor (ignition module) pin-outs which sends an earth pulse to the ECU, to tell the ECU when to send a pulse to the coil aka spark, if these are not correct, there will be NO SPARK.

I got your PM xmaster19, tried to PM you back "a long time ago" but you're settings on mx6.com are preventing personal messages (PMs).

Next week I'll have more time to verify the pin-outs.. unless you get there first.. LOL
Well I got my engine to *fire up* with my KL47 ecu and your pinout. It actually fired 4-5 times before it shut down and wouldn't fire up anymore, until I unflooded the engine, then it would do the same. My issue is mostly related to spark strength (getting weak spark from my coil, have replacement in hand but hadn't had time to put it in yet) or fuel quality (car hasn't moved since august of last year, same cheap fuel is in it since then which smells foul), or both. Will need to drain tank and replace with fresh fuel, will also replace my coil at the same time. I should come around to do all of that this weekend.

Point is, your pinout was correct and 4N pin should be the correct pin for ignition control. Use the procedure I provided in the other thread (crank no start) to test for ECU control.

If you're still trying to use the KLK1 ecu, you won't get spark control ever. You'd need the actual immobilizer unit from the same car the ecu rolled of Mazda with, with the correct chipped key and chip reader. If you don't have those in hand, it is possible to rewrite the immobilizer codes but it requires soldering a computer connector to the immobilizer chip inside the ECU and some reprogramming, which seemed like a waste of time as you will still need an immobilizer unit, chipped key and chip reader thingie. Again, the KL47 ecu is an easy solution that doesn't require rewiring anything.

Another detail, there is only one CKP sensor, the connector is located next to the water neck, the sensor next to the crank pulley. It is a VR sensor, it creates it's own AC voltage. Very easy to test with an AC voltmeter.

The sensor in the dist is the CMP sensor, it is a hall effect sensor, it actually pulls to ground the 5v ref the ecu sends to it.

Another note, only the CKP sensor is needed for injection pulse, both CKP and CMP signals are required for ignition pulse.

Hope this helps diagnosing your problem.
 

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Discussion Starter · #18 ·
THAT'S GREAT NEWS!!! THIS IS A WORLD FIRST! >:)

Yes that does help... I think I was looking at the same things. All the wording in the mappings are from various documents I could find.

Did it run until you turned off the key? Idle OK?

I replaced my coil, and it did NOT fix my issue, see the URL links in my previous post. Weak or no spark was the stator module [#13 in the picture] which detects the position of the Cam as the rotating vane breaks a magnetic field in the distributor..


The 1994 MX6 I was "experimenting on" for an ODBII conversion, is back in Australia, I am now in the UK, the now "running" MX6 (with original ECU), starts on first crank, runs really well. The down side is it is ATX!

I haven't got the KLK7 ECU here to try it out. :frown2:

Thanks for all your hard work, keep it up.
 

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My previous issue was timing, for some reason the engine I bought had the timing belt put on incorrectly, as one cam gear was phased 45 degrees, the other closer to 125... Fixed that but the car wouldn't run on it's own. Unplugged the MAF and while it ran like sh*t, it actually ran!

The car keeps running as long as I give it some gas, with the MAF unplugged. Scanner says my MAF reads 0 all the time (checked the scanner while the MAF was still plugged in, dah). I looked at the wiring diagram to confirm my MAF wiring and they are all confusing at best. There are depictions of a plug for the maf, but it doesn't tell you if it's the connector or the component plug and from what side it should be seen on. Pretty sure I inverted 12V and GND. I already repinned it but still need to test it and fear frying ecu circuits...

I'd need a solid answer on this, could you help me with that?

On this pic, from left to right, pins should be :

https://ae01.alicdn.com/kf/HTB1bxSW...7-MAF-for-Mazda-Millenia-2-3L.jpg_640x640.jpg

1- 12V, signal, GND

Or

2- GND, signal, 12v

???

Feels so close now, so many details to manage but much closer to running it now!
 

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Discussion Starter · #20 · (Edited)
I thought this may have be an issue... You are right to suspect the MAF!! That is EXACTLY what will happen if the signal is not being picked up properly by the ECU.

The old VAF has two parts the .. one for measuring the volume of air (variable resistor) and the temperature. The MAF swap requires the addition of a temperature sensor .. but you probably already know that.

There isn't +12V at the VAF!

The MAF needs a good (high current) 12v supply as it heats a filament. Air passes by the heated filament to create the signal back to the ECU. I tapped into the 12V that goes to the front heated oxygen sensor just below the exhaust manifold at the front of the engine. The connection can be made near the fuse box, from memory. Follow the wires back, use a multimeter to check for+12V. The MAF should be straight forward, +12V, GND, Signal .. So should the temperature (IAT) sensor, 2 wires.

I found this

http://www.performanceprobe.com/forum/showthread.php?t=40512

I will take a look too...

Where are you in the world? I am in the UK.
 
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