I have a Power Shot. I have a Power Shot S3IS (purchased 11/30/06). When I turn the camera on, I

Question

I have a Power Shot S3IS (purchased 11/30/06). When I turn the camera on, I LCD monitor and view finder remain dark. By tinkering with switches I can sometimes get them to work....often for only a few seconds...can the camera be repaired....is the warranty still good...(the camera was purchased at Costco. Need help. Thanks.