YOU don't want the customer service folks to run roughshod over you but you don't want to make impossible demands either.

Here's when you...

Must pay for servicing:

Brands like Sony Ericsson and Nokiawill fix your faulty phones without charge during the warranty period.

This is provided there wasn't negligent usage such as dropping your cellphone into a toilet bowl. In such cases, you'll have to pay the service fee, usually $25 and above, depending on the severity of the problem.

Cosmetic problems such as scratches or discolouration on the cellphone body or casing are not covered either.

Users are liable for such "fair, wear and tear", say lawyers.

Can request for a replacement:

Some mobile phone brands such as Samsung will offer the customer a replacement phone immediately if the handset is irreparable during the warranty period.

If the mobile phone is no longer under warranty, Samsung may offer the customer a special deal on the purchase of a replacement phone or on an upgrade to a new model.

Can request for a refund:

In cases of, say, a software glitch, which you had no hand in causing, brands like Nokia will exchange your phone with another handset.

But if even the replacement cellphone does not resolve the issue, talk to the company for a refund.

A lawyer from Chris Chong and CT Ho Partnership said that to obtain a replacement unit, users must provide evidence.

"Evidence includes reports that the manufacturer gave you when you brought the phone for servicing. This proves that the phone is faulty from the start," he said.

If the dispute persists, take the matter to court.

This is what sales manager Tan Geok Hoon did, last year. The 43-year-old successfully enforced a Small Claims Tribunal order against Nokia to pay her $778 for a handset that would not power up.