How is the mileage stored on Gen 1 Tacomas

I recently had my ECM meltdown and it took out the speedo, tech and odometer on the instrument housing. I found a replacement instrument housing, but have not been able to confirm if the mileage is stored from the ECM, the instrument housing or somewhere else in the truck. Some of the instrument housings I see online, list the mileage shown on the odometer prior to being removed from the vehicle and if I'm hoping to not have to have a drastic mileage increase from what my truck showed prior to the original ECM going down.

I have a 1999 3.4 v6 4x4 w/ a manual transmission if that makes a difference in how the mileage is stored.

 

It's just stored on the odometer.

 

Any idea if I can get the odometer reprogrammed to show the correct mileage?

 

@mechanicjon does this sometimes for folks

 

The mileage is stored on an EPROM chip on the odometer module on the instrument cluster. To remove it, it’s two screws and a ribbon cable - that’s all it is. If you’re confused which one is the Odometer module, it is the actual screen on the cluster. Just follow where it is and you can remove it easily.

 

On it. I PM 'd him.

 

@mechanicjon can you do this for me as well?

 

I’ve got a ‘99 2wd MT 2.4, originally with a non-tach cluster at 214k, now with a ‘99 tach cluster with 126k.

While I love the tach, I’d also like to keep the mileage history clean.

Can the EPROM be swapped between the two? The original cluster had a “mechanical” odometer readout, but no cable drive. The tach-equipped cluster is all electronic, and installed with no problems.

 

yes

 

it can be swapped or reprogrammed.

 

Well, that’s good news!

I’d seen videos and articles describing a reprogramming process that involved unsoldering a chip from the cluster, building a socket interface for a laptop and using octal code to correct the mileage. Looked fairly complicated, and a local speedo shop quoted hundreds of dollars, weeks of time and no warranty on the work.

on the other hand, if a simple component swap is possible between two functioning clusters, is there a write up or tutorial on how to do it? Or a service shop who can do the work reasonably, time and expense wise?