Gasboy Fuel Point PLUS Vehicle - Manual (Page 126)

Fuel Point PLUS Vehicle Installation and Configuration Manual 126
APPENDIX A
FINDING DP CALIBRATION FACTORS
FOR NEW OBD-II VEHICLE MODELS
A-1.
GENERAL
This appendix describes the procedure for finding out calibration factors of DP/μDP units' (PN:
µDP - 800907430/31/35/36, DP – 800907300/330/541) odometer reading for new vehicle models
equipped with OBD-II systems.
Calibration is required since in OBD-II vehicles, the Odometer is not available on the vehicle bus
interface and in has to be calculated from the velocity reading. The conversion formula has two
calibration factors varying between the various vehicle types and models:
Offset
Factor
The calibration factors' default values achieve an accuracy level of up to 3% error. To obtain higher
accuracy (up to 0.1%) it is required to find the appropriate calibration factors for each vehicle type
(make/model).
The process of finding the calibration factors includes four main steps:
1. 5km drive in low speed to find the Offset value
2. Programming the DP/µDP with the above Offset
3. Letting the vehicle drive for a few hundreds of km
4. Recalibrating the Factor based on the actual odometer reading
A-2.
DP CALIBRATION PROCEDURE
In order to calibrate the μDP/DP odometer reading, proceed as follows:
1. Drive the car until the trip odometer digit after the decimal point advances by one position
and stop the car immediately
2. Read and write down the μDP/DP Odometer (Start_Odo) and Odometer Fraction
(Start_Fraction)
values using the WP (see Table A-1, steps 11 & 12)
3. Set the unit Factor and Offset values as follows (see Table A-1, steps 9 & 10):
Factor: 7200
Offset: 0
4. Drive the car for 5 km at 10 km/h, without stopping while measuring the trip time with a
chronometer. Stop the vehicle when the trip odometer digit after the decimal point advances