1. A method of detecting faults in a lead of an implantable medical device, an electrode being positioned with respect to the lead, comprising the steps of: sensing electrical signals with the electrode; obtaining a signal function based on the electrical signal; applying a wavelet transform function to the signal function to obtain a plurality of highpass wavelet values and a plurality of lowpass wavelet values associated with the signal function; then applying a wavelet transform function to an immediately preceding plurality of lowpass wavelet values associated with the signal function to obtain a subsequent plurality of highpass wavelet values and a subsequent plurality of lowpass wavelet values associated with the signal function; then repeating at least once the applying the wavelet transform function to an immediately preceding plurality of lowpass wavelet values associated with the signal function; calculating a dispersion of the lowpass wavelet values; and identifying a fault in the lead of the implantable medical device based, at least in part, on the dispersion of the lowpass wavelet values.