Many service contracts and warranties carry a condition that you keep the item maintained in a stated way. The condition is often in a short clause near the end of the paper, not on the cover. When the condition is not met, a claim can be reduced or refused. Learning to recognise the clause early is far cheaper than learning it at the repair counter.
The list to make
Take the paper and list every upkeep duty it names. Mark each one with the words it uses, such as a schedule, a manufacturer recommendation, an annual check, a fluid or filter change, a cleaning, or a professional inspection. Next to each, write who must carry it out, what proof the paper accepts, and how long you must keep that proof. A duty written as whatever the manufacturer recommends has no fixed list, so ask the administrator for the list in writing before you rely on it.
Early warning signs
Recognise the problem early when you see any of these. The paper requires upkeep but does not say what counts as proof. You have no service log for the item, or the log has gaps. The item was serviced by a person the paper does not name. The upkeep schedule changes when the contract renews. The repair shop asks for records you did not know you were meant to keep. Each of these is a point to settle before a fault appears, not after.
Questions to ask in writing
Ask which upkeep duties are conditions of the claim and which are only advice. Ask what happens if a duty is missed for a short time and then done, and whether the paper treats that differently from a duty never done. Ask whether a receipt, an invoice, or a photograph of the work is enough proof. Ask who checks the proof and how long they have to answer. Keep the answers with the paper.
Keeping the trail
Put each service in one folder with the date on the receipt, the usage reading where the paper uses one, the name of the person who did the work, and any part references printed on the invoice. Keep the folder for as long as the paper requires and for a while after the contract ends, in case a claim is reviewed late. This is an ordinary record habit, not a legal opinion, and the paper's own wording decides what counts.