Laser Diode Coherent OBIS
Every diode has a different voltage, threshold and slope. So the OBIS would need to be recalibrated to work correctly with the new laser diode. Also with a new laser diode the fan angle and pointing is different so all the optics need to be re-optimized.  And then you need to confirm polarization, azimuth and other factors.  Why not send it back to Coherent for service?