Is this picture showing an OBDI or OBDII ECU?

daryl · Post by **daryl** » July 28th, 2006, 12:12 pm

Is this picture showing an OBDI or OBDII ECU?

I'm guessing that it is OBDI but not sure.

Post by **Custommx3** » July 28th, 2006, 12:25 pm

Not sure on the Pinout.. but the mx-3 obdi ecus are 3 plug.

daryl · Post by **daryl** » July 28th, 2006, 2:11 pm

Yeah I heard that OBDI has 3 plugs and obdII has 4 plugs, but I did not know what they meant by that and was trying to confirm that those plugs circled are the correct ones to count???

cjthor · Post by **cjthor** » July 28th, 2006, 4:48 pm

Custommx3 wrote:Not sure on the Pinout.. but the mx-3 obdi ecus are 3 plug.

ummmm mine has 2 plugs i think....94 obd1

daryl · Post by **daryl** » July 29th, 2006, 2:55 am

I need to know for sure if it is OBDI or OBDII before I buy the car.

If you know anything about ECU's can you take a look and let me know.

Can you tell by the numbers on the ECU?

Or by anything under the hood?

How else can you tell if a car is OBDII

daryl · Post by **daryl** » July 29th, 2006, 3:25 am

The reason I am asking these questions is because I am going to buy an MX3 today from a guy who has two 1995 MX3's for sale.

In the UK that is the year they changed from OBDI to OBDII so I need to know how to tell if an MX3 is OBDI or OBDII

So how can I look at an ECU and tell if it is an OBDI or OBDII MX3?

FlyVFR · Post by **FlyVFR** » July 29th, 2006, 3:45 am

Check diagnostic connector.

daryl · Post by **daryl** » July 29th, 2006, 3:54 am

I just found out that you can tell by checking for a diagnostics connector under the dash somewhere that looks this:

I am still interested in knowing to tell by looking at the ECU just to make sure i gan get it right when I go to buy the car!!![/url]

daryl · Post by **daryl** » July 29th, 2006, 4:04 am

You can tell by looking under the hood

LOOK UNDER THE HOOD. The diagnostic connecter should be on the right hand side by the firewall if your looking at the car from standing in front of it. If its under the hood its OBDi.

LOOK UNDER THE STEERING WHEEL BY YOUR FEET. If there is a diagnostic connector there than it is OBDii.

daryl · Post by **daryl** » July 29th, 2006, 4:30 am

SOME INTERESTING FINDS ABOUT ECU's and OBD.

I found this info on another post.(its not written by me)

I've been doing some more research on this subject. Up to now, I've always assumed my '97 model was OBDII, because it has a four-connector ECU and it's a '97.

But it turns out that it has no Diag Connector 2 under the dash, the FEN terminal in the diag connector under the hood is populated, and ECU connector #2 has nothing plugged into it. Now the things which plug into connector #2 in the four-connector K8 ECU on the Canadian '96 model are the extra O2 sensors and the EGR boost sensor, which are additions for OBD2. So my car is NOT OBDII. ##It's an OBDI with a four-connector ECU.##

I don't know whether this applies to all late-model European MX-3s, but its a fair bet, as, to the best of my knowledge, European governments did not require OBDII; it was at manufacturers' discretion. I think it's likely to apply to the KLDE cars as well.

What would this mean for swapping in a KLZE? Well, connectors #1, #3,and #4 on the four-connector ECU have the same numbers of pins as #1, #2, and #3 on the three-connector ECU. So, maybe you can just plug in a three-connector KLZE ECU? Not quite, if it follows the scheme in the '96 Wiring Manual. There are about 18 changes to make out of 58. But it could be manageable. Can you just plug in a four-connector KLZE ECU (KL62)? Not if it follows the scheme for four-connector KLDEs - you'd have to change 57 pins out of 58.

Now when did the change from three-connector to four- happen? There are two possible dates according to the Parts Catalogue, the first given as 941201 and the second not given, but some time before 961101, when the part changed from K857... to K861...

SO WHAT I THINK THIS IS GETTING AT IS THAT YOU CAN GET CARS IN THE UK AS LATE AS A 1997 THAT ARE OBDI BUT DUE TO A DIFFERENR WIRING SCHEME THEY ARE STILL NOT GOOD FOR THE KLZE SWAP, AND THAT YOU CAN TELL THESE CARS BY A K861 ECU.

I know for a fact that one of the cars I was going to look at has a K861 ECU, so that would mean that it is not worth buying as I intend to do a KLZE swap?????

daryl · Post by **daryl** » July 29th, 2006, 4:37 am

I have a problem now.

I just called the guy selling the MX3's and got him to give me the numbers on the ECU of both cars.

It turns out they are both K862

from reading the info in the last post, does this mean that it could not have the OBDII connector under the dash but still be the wrong car to use for a KLZE swap???

daryl · Post by **daryl** » July 29th, 2006, 4:57 am

Has anyone got a picture of an MX3 OBDII ECU so that I can look at the difference.

Also a picture of an ECU that is deffinately OBDI would be great.

ariesdude · Post by **ariesdude** » July 29th, 2006, 1:16 pm

Have you tried calling your local mazda dealer yet?

hgallegos915 · Post by **hgallegos915** » July 29th, 2006, 5:53 pm

wow that sucks.. so with obdII u cant just swap out the ngine block? :S eew

Spinkx79 · Post by **Spinkx79** » August 8th, 2006, 5:41 pm

I have a '96 OBDII with 4 connectors and the ECU model is K853-B.

And FYI there are different versions of the same models look for a letter.

On the 94 MX-6 ls OBD1 MTX ECU the model # is KL57-D.

MX-3.com

Is this picture showing an OBDI or OBDII ECU?

Is this picture showing an OBDI or OBDII ECU?

Yeah I heard that OBDI has 3 plugs and obdII has 4 plugs

I'm still stuck

You can tell by looking under the hood

problem

ecu pics needed