Switch on the ignition
Insert the test lead of the diagnostic module into socket 7 of module A
Press the test button on the diagnostic unit four times briefly but firmly
If the LED illuminates and stays illuminated, the system is ready for code input
Now You have to enter the code for resetting the servise interval counter, which is 1-5-1
To do this :
Press the test button once and release it; wait for the LED to illuminate again, then
Press the test button five times
When the LED illuminates again, press the test button once
When the LED flashes several times in succession, the code has been successfully entered
The service interval counter should have been reset

1995 850 glt n/turbo
111.000 miles

“I followed the instructions from Bay13 on turning key to II, connecting to #7 and pushing 4 times, then 1-5-1, but it's not working. Is there something else I need to do? I tried it about 10 different times, still nothing.”
First you have to read all the codes before you can reset the service light, give that a try
--
Winston 94 850 T W

hi,
are you sure it has a vdo combi type dash with a service light that is computer reset? some models had a yakuzi (probably spelt wrong) dash that had a little rubber bung in the plastic screen and you had to remove the bung then press a reset button under it with a fine screwdriver etc.. to reset the light.

steve.