• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Video Tutorial: Reprogramming 1997-2001 Digital Gauge Clusters

Alexia

NAXJA Forum User
Location
Huntsville, AL
It took $250 in new tools, four different clusters for tinkering, and some video editing to get this all put together. With this clusters can now be reprogrammed when repairing, replacing, or swapping without visiting a professional shop.

I have not yet figured out how to get odd numbered mileages programmed, but being off by one mile for the final result is insanely minor.

If I can get a police package cluster or a KPH cluster then I can start figuring out if any cluster can be programmed to different maximum MPH/KPH readings. Then it would be possible to swap brand new gauge face plates with different MPH/KPH readings with what people want.(Such as the ones Azzy's Design Works prints.)

Tools Needed
  • Computer running Windows XP, Vista, 7, or 8
  • SOFi SP8-B Programmer - Average $60 on eBay
  • SOIC8 Test Clip - Average $15 on eBay



Example mileage: 162,000
First entry will be 1620 followed by 1619 x49.
If the second entry is updated to 1620 then the mileage rolls over to 162,002. Each of the extra 49 positions increments the last two digits of the mileage +2 to a maximum of 98.

So how is exactly 0 miles set? By setting the first entry to 0000 and the remaining 49 entries to 9999. Since 999,99xx is technically the mileage before 000,0xx.

gallery_1_10_5960.png


Reprogrammed a dumb cluster to 98 miles.
gallery_1_12_154823.jpg


This is what happens when the EEPROM is completely erased or fried. This one was recovered from a backup ROM to its original mileage.
gallery_1_12_146262.jpg
 
Last edited:
You're the best!!
So a '97-98 cluster is different than a '99-01 cluster and 2000 cluster and are not interchangeable due to the ground wire different location?
 
Alexia-
Now can you work on the TCU? Change the rpm shift points?
 
Minor point - 0x31 is the record separator character in ASCII. That's probably why they used it to terminate each VIN number field.

edit: no it isn't, I am an idiot and looked in the decimal column not the hex column on the chart I used. Then realized 5 seconds after hitting 'post' that 0x30-0x39 are numerals so how the hell could it be a record separator control code? :dunce:

This is great work, thank you very much for posting it.
 
Outstanding work. Thanks for posting.


hot damn!!!!! amazing work!

Thanks! :D

You're the best!!
So a '97-98 cluster is different than a '99-01 cluster and 2000 cluster and are not interchangeable due to the ground wire different location?

They can be swapped, but there are a couple minor differences.

If a 1999 to 2001 is put into a 1997 to 1998, the Lift Gate Ajar light will be always on since it is permanently grounded. If the factory security alarm goes off it will flash the Low Washer Fluid light. When the washer fluid does get low it completes the ground circuit.

If a 1997 to 1998 is put into a 1999 to 2001, the Low Washer Fluid light will be always on since it is permanently grounded. Opening the lift gate will complete the other ground for the cluster. The security light will turn on when the washer fluid becomes low.

Either way, the clusters will run without the second ground wire, but obviously it is not recommended. I rewired my 1997 harness in the dash by swapping two wires between the connectors and moving one pin. Another note, swapping a 1999 to 2001 into a 1997 will remove the ability to see a flashing Security light on the cluster since the newer clusters use the CCD bus for this.

gallery_1_12_123027.jpg


gallery_1_12_162857.jpg


gallery_1_12_319951.jpg


gallery_1_12_289330.jpg
 
Alexia-
Now can you work on the TCU? Change the rpm shift points?

Maybe! I know nothing about their internals and have none to work on. LKQ charges anywhere from $20 to $50 for computers and generally when comes to their Group 1 through 5 pricing system they always charge the highest. Unless I can acquired one for free or cheap as a spare I really have no plans to work on that.

Minor point - 0x31 is the record separator character in ASCII. That's probably why they used it to terminate each VIN number field.

edit: no it isn't, I am an idiot and looked in the decimal column not the hex column on the chart I used. Then realized 5 seconds after hitting 'post' that 0x30-0x39 are numerals so how the hell could it be a record separator control code? :dunce:

This is great work, thank you very much for posting it.

Yeah, little odd to use 0x31 as a separator, but it works.
 
I have a 120MPH police cluster in my hands now. Bad news, it is a 1998 split year bastard PCB. Comparing it to my 1997 and 1999 cluster is only partially useful. Good news, the bits I have yet to identify are significantly different than the surrounding years. However, if it is just the version number like I suspect then back to the original plan of comparing PCBs for the difference.
 
Do you know if it is possible to download the eprom data from a “dumb” cluster and upload it to the eprom on the smart cluster? I see in your post above you mentioned there is a section of the data that is different for dumb vs smart clusters (0015 vs 00D5). Would I need to change those values from 0015 to 00D5 before uploading to the smart cluster? I am looking to swap out my dumb cluster, but keep the miles/vin the same on the smart cluster.

Also any chance you still have that video posted above? It looks like it is no longer available.
 
That is a good point, I will try to edit the data on the smart cluster to just change the vin and mileage to match the old cluster.

I will report back once I try it out. I am still very new to programming EPROMs so this will be interesting…
 
Back
Top