Error Name: Unhandled Exception. Why I am getting this error?

Hi,

ERA log is informing about error "Error Name: Unhandled Exception" on second line....

if (deviceSettings.paceUnits != 0) { // UNIT_METRIC = 0
vTemperature = ((vTemperature * 1.8).toNumber() + 32); }

vTemperature is declared as hidden var vTemperature = 0;  

Thanks in advance,

Oriol