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Timing Belt vs Drive Belt
A timing belt keeps the crank and the cams in step. A drive belt runs the alternator and other accessories. Replacing one does not service the other.
Timing belt vs drive belt is a mix-up that shows up on invoices. Both are belts. Only one of them times the valves. The other, often called a serpentine belt, V-belt, or accessory belt, turns parts on the outside of the engine.
They do not share an interval. A new drive belt does not mean the timing belt was done. A timing belt kit does not mean the belt you can see at the front was replaced, unless that line is on the bill.
Some engines have a timing chain, not a timing belt, and still have a drive belt for the accessories. The chain does not make the outer belt permanent. Each part follows its own line in the manual.
What the timing belt does
The timing belt, or cam belt, links the crankshaft to the camshaft. It is usually behind a cover. You often cannot inspect it by opening the hood and looking at the front of the engine.
Its replacement is a scheduled job: a distance, an age, or both, from the maintenance chapter. When to replace a timing belt is that decision. Stretching past the limit is how an interference engine gets bent valves.
What the drive belt does
The drive belt loops around the accessories: alternator, power steering pump, air-conditioning compressor, and sometimes the water pump if that pump is not behind the timing cover. One serpentine belt may do several of these. Older layouts use more than one V-belt.
When it fails, the usual result is a lost accessory: a charging warning, heavy steering, no cold air, or overheating if that belt also drove the water pump. It does not, by itself, throw the cam timing off. That is the timing belt's job.
Cracks, glaze, or noise are reasons to have this belt checked. They are not a measurement of the hidden timing belt.
How to tell them apart on an invoice
Read the words. Timing belt, cam belt, and timing kit are the internal job. Serpentine, V-belt, accessory belt, and alternator belt are the external job. If the invoice only says 'belt', ask which one before you pay or before you log it.
Log them as separate rows when both are done, because the next due points differ. A drive belt replaced at 40,000 km does not reset a timing belt that is due by age.
Declined work stays declined. If the shop recommended a timing belt and you only bought the drive belt, the history should say that. The invoice guide is the line-by-line habit.
What to store
Two possible rows, each with date, kilometers, and cost. The timing row gets the next limit from the book, including age if the book prints years. The drive-belt row gets whatever interval you were given, or no invented one if nobody stated it.
RPMBase can remind you only from marks you set on the maintenance tracker. It will not guess which belt your engine uses.