Will the timing belt cause the check engine light to come on? 2000 Ford Focus?

Will the timing belt cause the check engine light to come on? 2000 Ford Focus? - 1

No. Timing belts are changed on time elapsed and/or mileage. If in doubt change it as failure may well destroy your engine. The check engine light may be one of a dozen faults. Pop into a Ford dealership and ask them to run a diagnostic check. That will cost a small amount but will save you wasting money with guesswork.

Get the codes read. Codes for the cam sensor and crank sensor might be caused by a timing belt that has jumped or a bad belt tensioner.

Most places will read the codes and give you an estimate for free

Depending on the engine design, yes. If your engine has a crankshaft and camshaft position sensor, a worn timing chain or belt can throw them out of sync and make the check engine light come on and store either a P0017 and/or P0018 trouble code. Cadillac Northstar engines, for instance, are particularly sensitive to this condition.

As the worn timing belt could knock the camshaft and crankshaft sensors out of sync and trigger a landslide of trouble codes as you shouldn't be surprised if you need a new timing belt to save thousands down the road if the belt breaks and destroys the engine.