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Mileage calculator for Rover 75 Instrument Pack

Hi all,

My Rover 75 has the dreaded 999999 mileage error and I'd like to have an attempt at fixing it - but to do so, I need someone who has some mileage calculation software to do me a little favour.

The mileage on these cars is stored in 2 places ... on an eeprom in the instrument pack and in the LSM (Light Switch Module).

Now, if the mileage on the Instrument Pack is less than 250km, then it will update it's mileage from the LSM.

So, all I need to do is know what value to programme into the eeprom for say 50 miles.

The other issue is where to programme it. And to do this, unless someone already knows, it would be great to have the values for 49132 miles as someone has kindly given me a dump of their eeprom as a reference.

Can anyone please help?

Many thanks, Mark

Reply to
marpate1
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No idea of its programming or where it would be stored but as for data storage If your eprom dump is in hexadecimal then you would be looking at

49132 =3D BFEC but that's only 16 bit giving a max of 65535 decimal So for a max mileage of 999999 you would need a larger storage I'm guessing 24 bit. So look for 00BFEC Hope this makes sense to you.

Oh and 50 decimal =3D 000032 hexadecimal.

Bob

Reply to
Bob Dodds

Thanks Bob,

Yes, it makes sense and is from where I started.

Sadly, the data on the eprom is encoded in some way which is why I need the output from something like the Tachosoft mileage calculator software :)

Many thanks, Mark

Reply to
marpate1

You might find more info by Googling for the same problem on a BMW E39 - I think they are broadly similar with much of the electronics.

Reply to
Dave Plowman (News)

=A0 London SW

Hi Dave,

Many thanks. Actually I have looked into the E39 and Tachsoft actually have this shown on their website

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But,the location given for the mileage there is set to 0x0000ff in theeprom dump that I have for 49132 miles ... so I think that they arenot the same.

I may have to stop being so tight and get someone with a T4 to do this for me whilst replacing the IPK too :(

Cheers, Mark

Reply to
marpate1

The following is given in good faith, don't own a Rover, information is untested etc. etc.

Mileage is stored at address 0040 in a 93c56 eeprom and is stored twice in immediate succession.

49132 calculates to 2CD6D411B98F so search for "2CD6D411B98F2CD6D411B98F" in the donor dump. 50 calculates to 2DA96410C63F

999999 calculates to 232D741E422F

Reply to
bweebar

Hi,

Many thanks. Sadly, in the valid (I am starting to worry that it may not be) dump I cannot see the mileage string at 0040. The contents are:

0000 0000 ffff 5e4c 2d54 1001 e0ac e0ac

The information is correct for the E39 though as suggested by Dave, so I wonder if I have something amis :(

Many thanks, Mark

Reply to
marpate1

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