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Speedometer swap, where is the mileage stored?

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YOUR RESEARCHSpeedometer swap, where is the mileage stored?

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Run so it'll just add more time

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Suggestion
The ECU only shows total hours run so it'll just add more time to the clock.
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Speedometer swap, where is the mileage stored?

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Leading evidence: 'Run so it'll just add more time' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Run so it'll just add more time' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

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Test electronics by fitting the c4 instruments

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Suggestion · Original poster
The car is in pieces and will be for ages, so I want to test my electronics by fitting the C4 instruments to my C2.
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Speedometer swap, where is the mileage stored?

Use when viewing cars

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Suggestion
Simple calculation to ascertain if a car has been clocked I used when viewing cars to buy when I hooked up durametric for over revs and faults etc
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Speedometer swap, where is the mileage stored?

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Run so it'll just add more time

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Suggestion
The ECU only shows total hours run so it'll just add more time to the clock.
Original post Read captured discussion
Speedometer swap, where is the mileage stored?

Test electronics by fitting the c4 instruments

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Suggestion · Original poster
The car is in pieces and will be for ages, so I want to test my electronics by fitting the C4 instruments to my C2.
Original post Read captured discussion
Speedometer swap, where is the mileage stored?

Use when viewing cars

No successful repair reported for this finding.

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Discussions that contain suggestions: 1

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Suggestion
Simple calculation to ascertain if a car has been clocked I used when viewing cars to buy when I hooked up durametric for over revs and faults etc
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Speedometer swap, where is the mileage stored?

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4 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

911uk: 1 discussions

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POST 1 / ORIGINAL POSTEROriginal post

I am doing work on the speedometer for my 996 project car. The car is in pieces and will be for ages, so I want to test my electronics by fitting the C4 instruments to my C2. My C2 is on 61k miles, the C4 on 192k. Am I right in thinking that the mileage is stored independantly in the ECU and Instruments, so if I swap them then any miles clocked up will show as a difference when swapped back? I don't mind that so much as distances will be negligible. What I don't want is for my C2 to think it is on 192k when I swap the instruments back. TBH I don't see how it can with knowing the connections between the ECU and Instruments, but thought it best to see if anybody else has insights from previous instrument swaps. MC

POST 2Original post

The ECU only shows total hours run so it'll just add more time to the clock. I'm unsure if the ECU will see the clock swap and throw a paddy though but you may have to calibrate the fuel sender/gauge as the two tanks are different?

POST 3 / ORIGINAL POSTEROriginal post

Not so fussed about fuel tank. I'll do a few miles. It is a simple voltage from tank to instuments. MC

POST 4Original post

Miles/km is stored on the instrument, only hours run and average speed is stored on the ecu. Simple calculation to ascertain if a car has been clocked I used when viewing cars to buy when I hooked up durametric for over revs and faults etc

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