Rod,

Have you inspected the speedo board for any suspect components?

 

@YahmiPower (Alex),

Have you made any progress on your tach & speedo problem?

 

George,
Yes, I inspected my speedo and found that TR6 had a little burnt looking mark underneath it. Following the List of parts available on this forum I went ahead and had tr6 and any of the capacitors that looked suspect replaced. I had some ETs on my ship do it for me. Now when I plug it back in the low coolant alarm comes on while tach, speedo, and odometer still don't work. I was hoping that maybe there was another connector or cable loose that goes to the cluster. I now intend on sending my cluster to get professionally repaired.Hopefully that will fix the issue.
Rod

 

Rod,

That's really cool to see a modified TR6 installed on your speedo board! What other components were replaced? Did your ET solder the new TR6 in the right orientation - Emitter leg connected in the right location? It may be possible that it could be backwards.

BTW, the buzzer also sounds when the tach hits over-revs. So when you hear the buzzer, do any other lights come on - like the low coolant light? The buzzer may be sounding because of a related issue with your tach.

Based upon those photos, C2, C4, and C6 appear to have bulged tops. That may indicate a problem. I also see some signs of a solder joint issue on C4 and C6. Post a few more photos of your board and I may be able to lend more advice.

 

George,

I have not yet. Got slammed with work and the Holidays and brother coming home from UK (He is stationed there).

Also dealing with some overheating problems and trying to source the problem - naturally this became top priority. I think it is due to small leak.. Ordered Thermostat and upper, lower, and both turbo hoses from Mazda. So will get this fixed and then move on to the Speedo, tach, and odo.

Hope all is well with your brother and you had a great holiday!

-Alex

 

Hi all,

Sorry its been a while since i've been on. To give you an update on my situation with the cluster, I have identified that the issue is in fact with the cluster.

The wiring is sending the correct signals to the cluster. I also connected it up to an aciliscope and getting constant reading from the speedo. The circuit board on the cluster seems to be ok as well. Its getting power. I also traced a number of components on the circuit board and there is continuity etc. There seems to be an issue with the tacho/speedo components themself so i'm trying to source a new one.

Thanks
Dennis

 

@rexhvn Dennis,

No worries and happy new year to ya!

What did you identify is wrong with the cluster? Did you find an open from the troubleshooting advice in Post #49? Or was it something else?

 

Alex,

Happy new year to you. Are you off to a good start this year? No worries on the speedo. You know where to find me when you are ready to tackle the speedo & tachometer.

 

Happy new year brother.

Yes I am - Just working a ton and waiting on some parts from Mazda. Going to just replace all coolant hoses and water pump while I have everything torn apart.

I got a steering wheel so considering ordering hub and quick release and doing that and cluster all at the same time as well - I live close to work so riding the bicycle hasn't been a bad way to commute!

How about you George?

 

Hi all,

Sorry to bring this thread back but a quick question. Can the odometer be taken out and replaced with another? Just want to keep the original km/miles on my cluster, that's all.

Thanks
Dennis

 

Dennis,

IC3 stores your odometer information. It can be swapped from one board to another and your mileage will be retained. Take a look at this link to show where it's at and a list of part numbers: Speedometer & Odometer Circuit Board Components ONLY Check out Post 4 for component location. Post 9 confirms that IC3 is the odometer storage EEPROM.

There is one caveat to swapping odo chips. From an electrical repair perspective, it is easy to perform. De-solder the chip from the bad board then solder it to the new one. From an administrative perspective however, it may be considered odometer fraud because you are physically altering odometer components, such as the "storage bin" where the odo information is stored.

Without getting into a discussion about the legality of chip swapping, just know that such a potential exists. If you decide to swap the chip then document the occurrence to cover your ***(ets). When/if you decide to sell the vehicle then make sure to disclose that repair to the potential buyer.

Did you get a replacement speedo? I thought we were still working on the troubleshooting procedures with your cluster?

 

Hey @Gen2n3 ,

Bringing this thread back to life. I replaced my cluster and everything was going well until today. My revs stopped working. I traced the issue to the main wire that sends the signal to the RPM cluster and found it isn't making the necessary contact between the connector and cluster. If I push the wire from behind the connector with a decent amount of force, the RPM gauge works. But as soon as I let go, it stops. If I don't put enough force, it's jerks around a bit.
I've cleaned the connectors and also the components it connects to behind the cluster using the tips you provided earlier in the thread but still not go.

Is there a way to ensure they are getting enough contact?

 

Dennis,

Thanks for the update. What do the wire harness connectors look like? What do the sockets on the back of the instrument cluster look like? By following my tips, did you mean that you bent out the flex print contact tabs on the instrument cluster sockets? These tabs should have a natural curl to them. They should "interfere" in the path of the wire harness plugs. Do not put any creases in the flex print because that may break the wafer thin copper trace sandwiched inside.