Try this first, and then the alternative way below:
1st way:
* The following steps must be completed with no longer than 5 seconds between each step:
* Make sure the trip meter is in T-1
* Turn ignition key to position 1
* Press and hold trip meter button until zero is shown
* While still holding the trip meter, turn key to position 2
* When original trip mileage returns, release the trip reset button
* Turn key to off

2nd way:
- Ignition to position I
- Press and hold in the reset button for the trip odometer
- Ignition to position II within 2 seconds.
- Hold the reset button for the trip meter pressed in until the original value has been reset.
A general yellow lamp will light when the reset button is released.
- Release the reset button for the trip odometer within 4 seconds (if not, it won't reset).
The instrument gives an audible signal when resetting has succeeded.
- If the trip meter is already reset, the reset button should be held in for a minimum of 10
seconds and a maximum of 14 seconds.

Please let us know which way worked. First was listed for 2001 XC (think it's the same though), and the other for '02 and beyond V70's.
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1998 S70 T5 Emarald Green Metallic, 2004 V70 2.5T Ruby Red, Previous Owner of Black '94 850 Turbo Wagon. My cars have been running so well lately they've got me worried.