16. TROUBLESHOOTING 16.4.5 APS (STARTING AID) SYSTEM ( ): Always contact your Komatsu distributor when dealing with these items. In cases of abnormalities or causes which are not listed below, please contact your Komatsu distributor for repairs.
2-118 Problem Main causes Remedy Engine does not start at all ‡ Clogged nozzle (dirt, precipita- tion of paraffin, defective nozzle) ‡ Defective glow plug ‡ Crushed, clogged fuel piping, fuel leakage ‡ Defective wiring ‡ Blown fuse ‡ Defective APS controller (‡ Clean, change to specified fuel, replace nozzle) (‡ Replace) (‡ Check, repair) (‡ Check, repair) (‡ Replace) (‡ Replace) Engine starts at once, but there is excessive white smoke or engine stops again ‡ Clogged nozzle (dirt, precipita- tion of paraffin, defective nozzle) ‡ Defective glow plug ‡ Blown fuse ‡ Defective alternator function (al- ternator output is too low) ‡ Defective APS water tempera- ture sensor ‡ Defective APS controller (‡ Clean, change to specified fuel, replace nozzle) (‡ Replace) (‡ Replace) (‡ Check, repair or replace) (‡ Replace temperature sensor) (‡ Replace) When load is applied, black smoke comes out and engine stops ‡ Defective APS water tempera- ture sensor ‡ Melted heater relay points (‡ Replace temperature sensor) (‡ Replace heater relay) APS monitor lamp stays lighted up and burner burns APS monitor lamp does not light up (this is normal when engine water temperature is 20°C or above) ‡ Disconnection in APS monitor, glow plug wiring ‡ Defective wiring ‡ Defective timer (‡ Replace) (‡ Check, repair) (‡ Replace) Burner does not burn ‡ Glow plug is not red hot ‡ See above “APS monitor lamp does not light up” ‡ Fuel is not being sprayed out from nozzle, or spray amount is too small fi Clogged nozzle (dirt, precipi- tation of paraffin, defective nozzle) fi Defective APS controller (fi Clean, change to specified fuel, replace nozzle) (fi Replace)