184 Maintenance, Inspection SystemDiesel fuel filterCheck the fuel filter for any water residueduring ea ch engine oil cha nge.We recommend that you consult y ourVauxhall Authorised Repairer.Illumination of A indicates wa ter in thefuel filter 3.Hav e fuel filter checked at shorter intervalsif the v ehicle is subjected to extrem eopera ting conditions such as hig h humidity(primarily in coastal areas), extrem ely highor low outside temperatures a ndsub stantially v arying day tim e a nd nig ht-time temp eratures.Coo lantDuring operation the system is pressurised.The temp erature ma y therefore rise brieflyto ov er 100 °C.The glycol-ba sed coolant providesexc ellent corrosion protection for theheating and cooling systems as well asantifreeze protection down to ap prox .–28 ° C. I t rema ins in the cooling systemthroughout the year and need not b echa ng ed.Use of certain a ntifreezes c an lead toengine dam age. We therefore rec om mendthat you use antifreez es that have beenapproved by Vauxhall. Anti freeze a nd corrosion prot ect ionBefore the sta rt of the cold weather season,have the coolant checked for correctconcentration using a calibratedhydrometer. We recom mend that youconsult your Vauxhall Authorised Repa irer.The antifreeze content must guaranteefrost protection down to approx. –28 °C . Aninsufficient concentration will reduce frostand corrosion protection. Add antifreez e ifnec essary .If c oolant loss is topped up with wa ter,have concentration check ed a nd addantifreeze if necessary.9 WarningAntifreeze is a d ang er to health; it musttherefore be k ept in the original conta inerand out of the reach of children.