I sent my instrument cluster to be repaired, they were able to fix the tach and speedo "standard problems," however they were not able to revive the odometer - it seems to be a permanent dark screen now.

So with the repair that was performed, at least now, I can pass a cop on the highway without worrying that I am going to fast.

But thinking about the Odo screen, I am wondering... does anyone know of a method I can use to occasionally tap into the OBD module or computer to see what the mileage is so I can know when to change the oil. Edit: apparently the mileage is stored on the gauge itself, and not on the computer? Either way, it cannot be read from the ODB1 port.

As a second option, does anyone know of a Satellite based Odo display I can add to the car? Edit: I have found a gps based speed/odo for relatively cheap. Although not a good technical solution and certainly not elegant, this may be the best idea for now.

I suppose a third option would be to buy a new speedo with odo and install that.

Anyone else have an Odo that could not be repaired? What did you end up doing?

Edit 2.
I found and read a thread that goes into the speedo/odo components in great detail. Far more detailed and technical than I could follow. So, I am pretty much back to leaving the stock cluster alone and installing a secondary gps based odo under the hood.

 

Mine was a bad capacitor that is pretty well documented on here. Though it would come on sometimes. I replaced it myself.

 

They said they replaced everything they could think of, all the caps that looked bad, and also the nearby ones that they suspected might be the cause of the trouble. No soap. I am thinking the screen itself is just dead.

I suppose I could always put a GPS speedo with odo somewhere in the car and use that. Though I hope I can keep a stock look.

 

Odo dead as Dodo. You can get a new speedo that matches very closely from Speedhut.

 

You probably read one of my threads. It sucks to hear that your speedo/odo still doesn't work after a professional couldn't fix it. You could get a replacement from Ray Crowe (if they are still available). You could get a JDM speedo then swap the faceplates and move 1 or 2 resistors. If you go that route, you would need to re-calibrate the speedo. DaleClark has a KPH to MPH conversion thread and a Speedo calibration thread.

As gmonsen suggested, you could replace the bad speedo with a Speedhut unit that is GPS calibrated.

Alternatively, you could post up some pics of your speedo in the FD Troubleshooting Speedo thread where I could offer advice.

 

Thanks Gmonssen, I'd thought about doing this too. but with my Speedo and tach working, I think this would be a drastic move because I'm guessing I would have to carve up the plastics and the modify the blue flexible wiring board (not sure what it is called) in order to get the Speedhut Speedo in? I think I will do this as my last effort. I did see the thread where someone replaced all of their gauges with the Speedhut units and I thought it was a gorgeous solution.

 

There's a guy named Geoff Pritchett in the "RX7" facebook group that can replace your bad LCD and refurbish the cluster.

 

Actually, I read a few of your threads... They had my head spinning. As a non-tech (electronics), I could follow along some of the things you were saying... but not many.

I looked at a JDM cluster. I like the fact it has a built in boost gauge and I appreciate that it can be modified to change from KM to miles. But there are two things that keep me from going this route.. (1) I don't like the white gauges, (2) the cost, by the time I find and pay for the gauge cluster, then pay to convert it to blackface, and convert to miles, I may be so far in and then in a couple years have to fix that one's caps too. So, for now, I will just go with my odo deficient cluster...

As for my cluster, I will take any pictures that may be notable when I get it back home.

Thanks again.

but wait...

This may be the last missing piece of the puzzle. Thanks

 

Thanks for the compliments on those threads.

I may not have been clear about the speedo replacement. You do not necessarily have to replace the entire instrument cluster. You would only need to replace the speedometer circuit board. You could install a JDM-type speedo board if that is the only one that could be sourced. The differences between a JDM and USDM speedo board are very minute. A JDM speedo board will normally have a black face and will have the same orientation of the numbers (180 kph is in the same location as 180 mph). The speedo faces are obviously different but the main board is identical, with the exception of the placement of 2 resistors. These 2 resistors configure the board to indicate either the English system (miles per hour) or the metric system (kilometers per hour).

Therefore, it is possible to replace a MPH speedo circuit board with a KPH speedo circuit board. In order to keep things right, the MPH face can replace the KPH speedo. However, the circuit board must be configured to measure the proper system - either English or metric standard. That is done by moving 1 or 2 resistors on the speedo board itself.

If you have that inclination to do such repairs then that's great! Otherwise, you may opt to have a professional perform that task. Fixing a speedo is no easy task because it does require a little trial and error. The main reason for this trial and error stems from hidden damage caused from leaking capacitors and the amount of time that leaked acid had to damage components along its slow path to the bottom of the board.

FWIW, the LCD itself is fairly robust and rarely fails. The root cause for failure could be any number of components damaged by leaked acid from those old capacitors. For example, this member cites a good example of damaged caused by bad caps: Constant Over-rev Warning Alarm. The start of Page 2 shows what damage it could cause.

I wish you the best of luck in your repairs. Please let us know how it all works out!

 

You mentioned the white faces on the jdm clusters.. they are available and more prevalent in black. The early model jdm cars were the same as the us clusters (visually) minus the units of measurement.


my 92 jdm cluster

 

AE_Racer,

Did you convert that speedo to MPH? I see a faint hint of the "mile" indicator in your odo's trip meter. Did you do the conversion yourself or have someone else do it? Do you have any other advice for BLKTOPTRVL?

 

I did the conversion myself. My odo was staying off and would pop on periodically. I changed a capacitor to fix the odometer and swapped it to mph and miles while I was in there. I didnt change the face either, just adjusted speedo so it reads mph on the kmh marks, 60kmh is actually 60mph. It was simple for me but I do have a decent amount of experience with a soldering iron.

 

That is encouraging! Thanks for sharing.

Keeping the metric faces on your FD still maintains the JDM look for your RHD car but eliminates the hassle of metric to English speed and odo conversions. I think that is a simple yet elegant touch of detail. Well done, sir!

 

Goerge, if you are still interested in pursuing the mystery that is my odometer, I have some more observations for you.

I received the cluster from the repair shop about a week or two ago, but delayed putting it back in until yesterday because I was waiting for an alternator to arrive in the mail. As the repair shop advised, the tachometer and speedometer were once again working when I started the car. The repair technician had indicated that they had done "all the normal RX7 repairs" which I take for stuff that you likely already know about.

What they could not fix was the odometer... no matter what they tried, they could not get it to come back to life.

So today, while test driving the cluster and my rebuilt alternator, I was happy to have the tach and speedo.

About 3 miles into my test drive, after I had parked and exited the car to do some grocery shopping, I came back and started the car again.

After rolling about 100 yards, the Odo sprang to life. (There was a small cheer from the crowd.)

I drove another 20 minutes waiting for the odo to go out again, but it didn't. It kept working all the way home and into the garage.

However, as soon as I turned the engine off, the display went dark again. I fiddled with the key trying to see if maybe the ignition switch was loose and maybe that had something to do with the dark screen. I turned the key repeatedly from off to on and nothing happened, the Odo would not come back.

I decided to come here to this website to leave this message for you, but then realized "I did not try starting the engine again." So, I went back to the garage to try that before posting.

This time, when I turned the key, and before trying to start the car, the odo came to life again. It had only been about ten minutes since I'd parked and shut down the car.

So, there is some intermittent thing happening here. I have no clue, but maybe you do.

 

BLKTOPTRVL,

That is an interesting odometer discrepancy you described. There could be an issue with the polarized capacitors, even though a professional looked at it. The "normal RX7 repairs" could reference the just got done figuring out how to fix an FD odometer thread.

I'll be happy to lend you a hand. At least we could figure out what's wrong with your speedo board together. Do you have any planned trips with it soon? Do you have any problems with removing and inspecting the instrument cluster? How are your battery cables? Are both positive and negative cables in good condition? Are they firmly attached to the battery? Do you have additional grounds connected to the car? Do you have any experience with a DMM (digital multimeter)? What about soldering - do you or do you have a buddy near by who could solder?

What I'd like to do is carry this conversation over to the Troubleshooting the FD Speedometer-Odometer-Tachometer Circuit Board thread. We can peel back as many onion layers as we can there.

In the meantime, please remove your instrument cluster and take out the speedometer board. Then take pictures of the board and its components up close. Also take some pictures of the back side of the board. I'd like to see the solder joints. You may have seen this thread: Alarm Buzzer above 2000 RPM. The photos provided in that thread were crucial in spotting suspect components. You don't have to recreate those photos but the idea is to show as much detail from several angles.

Do not worry about de-soldering the speedo face to access the board underneath it. For now, focus on external observations of the board. I'd also like to see the condition of your flexprint on the back of the cluster. Please show the condition of all the flex print connectors. There should be 5 total - 4 sockets that interface with the dash harness and 1 ribbon connector that goes to CON1 on the speedometer board.

As part of the preparation for this journey, disconnect the positive battery cable then press on the brake pedal for 10 seconds. This should discharge any capacitors. Once that is done, wait 10 minutes then reconnect the battery. You may start the car normally and observe what happens to the odometer. Even if it comes back to life, I will still need you to remove and inspect the speedometer board.

How does that sound?

 

George,

I think I mislead you. I posted those observations for your consideration - in case you run into someone else with a problem similar to mine and because you seem to have a deep and genuine interest in knowing and solving these cluster issues. For myself, at this time, I have a working speedo and tach, and apparently an occasionally working ODO. I sent the cluster out for repair because, no, unfortunately I do not have any of those skills you mention.

For now, I hope it will keep working as it is, if it does not, then I will look for another solution, but for now, I will carry on as it is.

Thank you again for the input and for the offer of assistance.

BTT

 

BTT,

Thanks for the added insight. If you would like to investigate your intermittent odo at a later date then you know who to call. Enjoy your working tach and speedo!

 

BTW, for anyone else interested... When the ODO is dead, so is the cruise control. I believe the opposite is true too - that when the ODO is displaying, the cruise works.

Edit: This may be false. Will get back on this.

 

did you ever get your odometer working again? You are correct that when the odo doesnt display the cruise does not work because its not actually the LCD thtats bad its the processor/processor circuit thats on the board thats bad and thus not controlling the odo, cruise, or coolant level light among other things...I can refurbish it for you if you still need as i just saw someone tagged me a while back in this thread so just following up with you.

 

Does any know how to contact Geoff Pritchett if he is still repairing gauge clusters

 

Not sure if he still repairs them, but you can try getting in touch with him on instagram @geoff_pritchett

 

Many thanks for your timely response. I have no social media accounts, so I guess I'll have to change that!

 

Does Michael Gagne repair these? He's on FB. There's also a guy in EU but I forget his name...