Why does the fan belt on my car squeal on start up?

My 2001 Toyota Yaris 1.3 SR has a noisy fan belt on startup but once driven for a couple of minutes it stops. My mechanic said it is because it has not been driven much lately?

Asked on 11 August 2019 by Dilys Warner

Answered by Honest John
He's right. The heavy work imposed on the alternator to put charge back into the battery is causing it to slip. A fresh belt will fix that.
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