Need help electrical guru's

[kylekizzle]

I have a 94' MX-3 that has been klze swapped. Since the swap the speedometer has not worked. Every other gauge in the cluster functions correctly. I changed clusters to see if it was the problem and it still didnt fix. I checked the pins on the back looked in the online manual even checked out my other mx-3 GS 92 and copied the pins as well as another car similar to mine, to no success. To my understanding the car was a RS before the swap and is now the 2.5L KLZE. Any ideas on how to get my speedometer to work? I have toyed with the idea of getting a older cluster that is cable driven and seeing if that fixes my problem, let me know. Thanks a bunch.

I found a post I made before, John helped me describe the problem so I mind as well add it since he added some valuable informatiom, unfortunatly 1 year later I have still come to no resolve and refuse to bring it to the morons at my local mazda shop.

Johns post is below from a earlier post by me.

Kyle has a 94 with a swapped in 92 dashboard. He's not sure if the instrument pod came along with the transfer. First we've got to determine if there are no technical/electrical differences between the 92 and 94 instrument pods, so confirmation from the community is needed on that. He's running a ZE MTX. As he has said he's installed a new speedo sensor believing that was the root of the problem. Apparently not because post purchase of new sensor has determined that the sensor test of the old and new sensor by turning the gear with a voltmeter on the 2 connectors has determined to be both serviceable. He has to do the subsequent test with a voltmeter on the 2 connectors that go to the instrument pod on the 12 and 10 pin harnesses. Has anyone done this before? I've advised him that if no current is present than it's between there and the sensor, which I think will be highly unlikely.

[DJsMX-3]

Did you make the change with another RS or GS cluster?
If you just tryed another RS cluster it still wouldnt have worked if the car is a V6 now...

To the best of my understanding no of the GS clusters use the geardrive but function electrically AND the RS'es uses geardrive to the cluster.

So for it to work probertly with a K8/KLDE/KLZE/KFZE engine you need the GS cluster instead of the RS cluster, and you need to check the online electrical wireing manual to find the trannysensor on the GS and check that it has been connected to the wireingloom.

Then just use a simple ohmmeter and check theres a connection from sensorwires to plug behind the cluster and if theres not then mazda didnt run thoose wires since if was build as a RS so you fix it by running your own wires from sensor to cluster.

Let me know if it helped anything or what you find out

[jschrauwen]

Well that makes sense DJ. If after the wiring from the sensor is routed through the RS's wiring harness the terminating pair will not be coincident with the connector at the back of the instrument pod. Using a GS instrument pod and determining the pin connections to the back of it that would normally go to the GS speedo sensing unit. Once you've determined the colour code from that instrumnet pod wiring connector that applies to the GS speedo than run separate wires to the dash area from the speedo sensor and disconnect the pre-existing wires to the speed for the Rs connector and attach the new wires from the speedo sensor. I hope that makes some sense.
Dj, is that the same sort of lines you were thinking of also?
Kyle, we got to get you up and running for this summer. Need you to join in on the fun down here too. Hope this helps a bit.
John


*Edit*
Brain fart here. There's probably not going to be any connection (or pin connections) on the RS instrument panel connector because it never had any electrically controlled speedo, so part of my previous statement won't work. The separate lines would have to be routed from the sensor to the GS pin connections on the back of the GS pod, if possible. If that isn't possible than another alternative is to do a complete transferrance of the wires from the RS pod connector to a GS pod connector. Swapping over each wire....wire for wire as they are situated in the connector and then the separate wires for the electricl speedo can be added to that pod connector. It's a bit of cutting and soldering but at least you'll get your speedo up and running.

[ariesdude]

Whoa Timeout here ..... As far as i know the SOHC (92-93) RS models have mechanical speedo and the DOHC (94-96) RS models have electric speedo.
Since yours was a 94DOHC model it should have an electric speedo (mine does). Have you checked if the speedo sensor connector is seated properly?
Also if you have your old RS sensor try putting it back in or get a new RS sensor. The electronic speedo works by counting the number of pulses sent by the sensor - i dont know if there is any difference between GS and RS sensor - but if there is, then the GS sensor would not send the correct pulses for the RS speed circuit.

[DJsMX-3]

Well if the 94 and Up RS allso has electrical speedo, then its a matter of checking if the plugs/wires to the cluster of GS/94RS is the same...

If they are then change to a GS cluster with a GS speedosensor.

Using the RS cluster and RS speedosensor in a GS tranny could give complete useless readings because theres the possibility that the GS trannysensor was directdriven and the RS trannysensor was driven by a secondary cog, or vice versa..

If you take the gauge bezel off and look at the bottom right corner of the speedo mine say 637revs = 1Km and its a GS speedo "you guys probertly have the same explanation in miles"

Do the same with your RS speedo and see how many revs equals 1 km/mile if yours is diffrent you should use a GS speedo for sure

[kylekizzle]

I have a question and answer actually.. Ok I checked my speedo, it has the same revs = 1km as you just mentioned. I think I have a solution to my problem, I have 2 different clusters, both from a GS I am pretty sure, I am guessing it dosent really matter the year, just that they are electronicly driven speedometers, anyway, my pin layout that goes into the back of my speedo, I tried it one way before and it burned the circut but then I checked on my other MX 1992, and copied the exact pin layout thats from the back of that car, but heres the thing I just realized, mine is a 1994 with a kl31 ECU in it. And I am sure my car was a RS 94 but since it has been changed to a KLZE Engine with a KL31 ecu. I am assuming the harness is the same maybe? I am unsure. But I will try this and see how it works. Let me know if you guys think im just stupid Maybe I am! Or maybe it is crazy enough to work !

[kylekizzle]

I am looking in the online shop manual for the pin configs for the insturment cluster for 1994 for the RS and GS layouts, but the page isnt loading. Anyone wanna help me out ?

[kylekizzle]

Ok, I have an update. I checked my cluster pins and they are set correctly, to the specifications I saw on http://eunos30x.com/info.html and everything is working correctly, the two cables that come directly from the speedometer into the back of the cluster both are connected correctly, I checked with a tester and the spots on the back of the speedometer are fixed( I rewired them and resoldered them ) and I checked with a tester, they also both work. Now I am completely stumped without any ideas on what to do next? Does the ECU connect to it anyway? Is there a wire I can check to see if its in the right spot on the ECU ?? ANYTHING!! HELP!!!

[DJsMX-3]

Did you check the speedosensor and that theres a connection from the plug of that sensor to the plug behind the cluster like i mentioned?

Allso check the simple things first..

Theres only 4 screwconnections comming out of the speedo, its all written right beside the screwterminals

With the speedo in and the car turned on check that the ground screw is good and that the speedo is getting power to the ignitionscrew, the speedopulse you probertly cant check that way unless you have a supertester that can measure the frequensy.
Then theres only the outputscrew left and i think its only a feedback to the ECU.

SO if the ground and ignition is good behind the speedo in the cluster then check the connection to the speedosensor in the tranny.

Havent ever looked at the speedosensor myself but its either grounded directely by its housing to the tranny, and if it is you just take a loose wire fron the sensor to the pulsescrew behind of the cluster...

Or if its a dualwire sensor you measure what wire in the plug "on the harness and not on the sensor" is connected to ground, and run a groundwire to that same wire on the plug of the sensor and then run the wire from the other connection of the sensorplug to the back of the cluster like mentioned before..

If none of this is working your cluster probertly is fried or the sensor is bad or the wrong type.

The more accurate you follow my instructions and give me feedback as to what you measured the bigger the chance is of getting this fixed.