The above error message (CAL ERROR ###/####) is a three or four digit number starting with a 1 or a 2. It indicates that the instrument has detected unstable measurements during the 5 calibration readings on the white plaque. Check the following before having instrument returned for service:
The instrument must be kept still during the white calibration. To ensure the instrument is not moved, you may place a dead weight on top during the calibration procedure.
The battery pack must be installed in the instrument and at least partially charged.
Have customer blow out the optics with low-pressure, dry air to eliminate dust.
If none of this helps, the instrument must be returned for service.