Hi


I am currently building a kit car in the UK that uses an mx5 as a donor car. I will be putting the car thought an IVA test (registering it as a new road legal car) and would like the miles to start at 0000000.


I am very aware that this is probably a do or die situation, so I already have a couple of spare boards to try some suggestions on.


So if anyone would have any ideas on how I can try and wipe the data from the IC and restore it to factory settings I would be very grateful.


Many thanks

Andrew

 

Do you really think it is that easy?

 

You would have to take it to the dealership and ask them to do it.

 

Do you really think it is that easy?

Hi GopherT

In a word, NO

I did level 1 microelectronics in collage a long long time ago so I know my way around a board, so I'm under no illusions that it is easy or even possible. From looking at the board I can't see any seral / comminution points, so I would say that it must be programed before assembly.

But my thinking is, because the board has three main functions, one to count the miles driven, two it has a basic mile trip counter that can be reset via a button on the board and three to display the information an a single line LCD display. So because its a generic counter, and you can reset the trip mileage there may be a redundant pin in the IC that could reset the main mile also !


So I thought I would let more experience eyes have a look and possibly come up with some suggestions before I destroy the board

You would have to take it to the dealership and ask them to do it.

Thanks for the reply

Unfortunately the board is from the dial assembly on a 1999 MX-5 and it has no fancy diagnostics unlike modern cars where the mileage is stored on the ECU and can usually be changed to whatever you like. I called my local Mazda garage and the response I got was "your having a laugh mate" so no help there. My only really hope is to try myself, so any other ideas would be well received.

Many thanks
Andrew

 

Hi GopherT

In a word, NO

I did level 1 microelectronics in collage a long long time ago so I know my way around a board, so I'm under no illusions that it is easy or even possible. From looking at the board I can't see any seral / comminution points, so I would say that it must be programed before assembly.

But my thinking is, because the board has three main functions, one to count the miles driven, two it has a basic mile trip counter that can be reset via a button on the board and three to display the information an a single line LCD display. So because its a generic counter, and you can reset the trip mileage there may be a redundant pin in the IC that could reset the main mile also !


So I thought I would let more experience eyes have a look and possibly come up with some suggestions before I destroy the board


Thanks for the reply

Unfortunately the board is from the dial assembly on a 1999 MX-5 and it has no fancy diagnostics unlike modern cars where the mileage is stored on the ECU and can usually be changed to whatever you like. I called my local Mazda garage and the response I got was "your having a laugh mate" so no help there. My only really hope is to try myself, so any other ideas would be well received.

Many thanks
Andrew

A simple "counter IC" is not used. It is a microcontroller that is specifically programmed to count, store and display the counted value to an LCD on the dashboard. The counted value is frequently updated to a non-volatile memory so that it is available for years after you reconnect a battery to it. If it were as simple as grounding a pin to reset the counter, the chips would reset themselves after a few hours, weeks or years without power. They don't.

 

A simple "counter IC" is not used. It is a microcontroller that is specifically programmed to count, store and display the counted value to an LCD on the dashboard. The counted value is frequently updated to a non-volatile memory so that it is available for years after you reconnect a battery to it. If it were as simple as grounding a pin to reset the counter, the chips would reset themselves after a few hours, weeks or years without power. They don't.

Thanks for the explanation.

Would the trip meter not use the same memory ? as that does not lose its mileage with the battery disconnect either but it has a reset switch.

Many thanks
Andrew

 

Have you thought about buying a new board? A new board would not have any accumulated miles on it.
These boards were designed to prevent people from falsifying the mileage on a used car, and if thousands of used car dealers can't beat it, you can't either.
But that brings up a new idea. Go ask the shadiest gits in the used car industry.

 

Hi #12

Nice idea about buying a new board but they don't sell it on its own only as a complete dial assembly and it's big money.

I am trying something different from those dodgy gits, i.e. reset it to zero and not reprogram it to a lower mileage. I think it might look even more dodgy trying to sell a used car with 0 miles on the clock .

but your post has given me another idea. The wiring loom is out of the car which I've been modifying to suit the kit car (two big bags of unneeded wire !) The loom is powered up so I can test the relays and connections, so if I can mimic the speed sensor which I think is a hall type.(I have a Jim stim to test my megasquirt 3x so that might do the trick.) I could possibly do a Ferris Bueller's day off but instead of going backwards I could go forward to 0000000.

Many thanks
Andrew

 

Generally the mileage is stored on one of the IC chips and should be read by a code reader. Most companies use Hex to program. If you can read the code, you can convert that to the existing mileage. You can then take the same code, and insert the necessary Hex value to program it back to zero. You would have to remove the IC from the board, have someone who knows how to program, and reinstall it on the board. I do want to point out that in North America, odometer tampering is illegal and can result in fines or jail.

 

I do want to point out that in North America, odometer tampering is illegal and can result in fines or jail.

I do want to point out, this guy speaks like a Brit and I can't imagine that building a car from scratch is called, "tampering".

 

I do want to point out, this guy speaks like a Brit and I can't imagine that building a car from scratch is called, "tampering".

Agree". I couldn't imagine going to the Pennsylvania dept of transportation (PennDOT) to get the license plates for my newly built car and listing 57538 miles.

PennDot lady: but sir, you said you built the car from scratch and are exempt from safety testing, how does it have 57538 miles.

OP: well, I built it with parts from other cars

PennDot lady: then it does not qualify as a self-built experimental vehicle - you'll need a certificate from a State Inspection facility

OP: well I can't get a state inspection because it has no catalytic converter and no air bags.

PennDot Lady: then you will fail the inspection, Next person please!

 

I do want to point out, this guy speaks like a Brit and I can't imagine that building a car from scratch is called, "tampering".

Just covering my ass. I believe they call this hacking an odometer. Where I come from, not legal. Anybody follows my advice, they are on their own. Never know who reads these posts?

 

Just covering my ass. I believe they call this hacking an odometer. Where I come from, not legal. Anybody follows my advice, they are on their own. Never know who reads these posts?

Really? Canadian Law: "Any person who builds any sort of vehicle and attaches an odometer which was altered to reflect the true mileage on that vehicle is guilty of a crime."
I can't quite get myself to believe that.

 

Canadian Law: "Any person who builds any sort of vehicle and attaches an odometer which was altered to reflect the true mileage on that vehicle is guilty of a crime."

That's the way it is in Ohio, or was last time I built a car from parts. After one nightmare with the building of a car(trying to get a title) the next one used the title of the car that had the most parts in it. No matter what it looked like, a 1970 model T.

 

I had one brush with this in the real world. I replaced most of the instrument cluster (and the transmission and a few other things) in a 1986 Areostar, and when it came time to swear under penalty of perjury that the odometer was correct, I made an "X" in the box below that sentence and thus swore the odometer was false. I did this right on the title for the car, in the DMV office, and nobody arrested me. In fact, nobody even complained.

I guess this experience gave me the wrong impression about how to deal with titles and the law.
If it's that difficult, I promise not to build any vehicles.

 

That is how it's done on a used car in Ohio too. It's when your building a "kit car" or "home built" one that it gets complicated.

And since it doesn't take much now days for an insurance company to "total" a car that can be repaired, they now have "salvage" titles. Those cars have to be inspected before a title is issued.

 

Agreed. Also based on experience in Ohio. Just say the actual miles are false and move on. Anyone who buys a homebuilt car will know it really doesn't matter. There is no "warranty."

John

 

since it doesn't take much now days for an insurance company to "total" a car that can be repaired, they now have "salvage" titles.

Reminds me of a Ford Explorer I met lately.
It wasn't a salvage title, but that was only an oversight.

 

Perhaps you have misunderstood me. Our laws state that an odometer must reflect the true mileage of the vehicle that it is representing. If the odometer gets turned back for any other purpose, you are breaking the law. I do speedometer/odometer work and I have a form that people have to fill out. One of the criteria is the correct mileage to the best of their knowledge. That paper is very important to me. CMA.

 

Perhaps you have misunderstood me.

I believe you are correct.
Starting with the context of this Thread, "I'm building a car that didn't exist before I made it and I want to get a used odometer to display the true mileage."

I do want to point out that in North America, odometer tampering is illegal and can result in fines or jail.

an odometer must reflect the true mileage of the vehicle that it is representing.

The first statement comes across like, "Any attempt to alter an odometer so it shows the true mileage will result in immediate criminal prosecution."
The second statement sounds like truthfulness is allowed by the Division of Motor Vehicles.