INFRA RED LIGHT IS ALWAYS ON
If it doesn't heat, and doesn't drain the battery, then I don't see how it can really be on... it takes a lot of power.
If you don't have a warranty on it, or a service plan with your provider, try reseting it. just save everything you don't want to loose before.
The soft-format code for Series 60 phones is *#7370# . You enter this code as you would enter a phone number in the Phone application. It performs a format of the Internal drive - All data will be lost if you use this feature.
Series 60 reset
The method of performing a hard-format, i.e resetting it completely to factory defaults and removing all data, is as follows:
1. Switch off the phone.
2. Hold down the '5' key, and with this held in, turn the phone on with the power button
3. Wait until a green tick appears over the right softkey, then release the '5'
4. Follow the prompt to reset the phone
Note that you shouldn't switch the phone off or remove the battery when performing either of these operations, and it's advised that the handset has a reasonable amount of battery charge before performing a format/reset.