Operating - ICM 15/ Engine hours Press this button to show the total accumulated engine hours worked by the machine. This function only records whilst the engine is running and cannot be reset. 16/17 Wheel calibration The ICM relies on an accurate wheel calibration factor being programmed in to enable it to display accurate information on ground speed and area covered etc. (Programming is covered later in this chapter). The instrument can be preprogrammed with two different calibration factors for different size wheels - e.g. Low pressure and row crop or, for extreme accuracy, different factors can be used for when working in soft/wet conditions and hard/dry conditions. One of the L.E.D indicators on one of the wheel calibration buttons will be illuminated at all times to indicate which one is in current use. To change to the other, press and hold the button down for approximately 5 seconds (until it beeps). 18/ Service intervals When you press this button two pieces of information are shown in the LH display window - the number of hours remaining to the next service and the type of service due next (F,A,B,C etc).   Service reminder When a service first becomes due the L.E.D indicator on the service interval button will illuminate and the the alarm will sound once only. The LH display will also indicate that a service is due. After that a reminder will show on the LH display each time the engine is started and the L.E.D on the button will show continually. When the appropriate service has been carried out it is then necessary to go into the instrument programming mode to reset the service interval reminder (see programming - later in this chapter). The L.E.D will then go out, the service hour counter reset and it will start counting down to the next service. The different service types (F,A,B etc ) are indicated in the service schedule later in this manual. 19/ Glow plug warning light The L.E.D will illuminate when the ignition is first switched on and will go out when the engine is ready for starting. For more information on starting see the starting section earlier in this manual. 20/ Alternator Warning light If this warning light illuminates whilst the engine is running it indicates a fault with the charging system which should be investigated immediately. 21/ Oil pressure warning light This warning light should go out within a few seconds of start-up. If it is still on after 10 seconds the alarm will sound and the LH display will flash "STOP" . The alarm will also be activated if the oil pressure becomes low at any other time when the engine is running. The engine should, of course, be stopped immediately should the alarm be activated and the cause investigated. < 14 >