JPS10 subwoofer capacitor replacement

I need to replace capacitor C103 in the Jensen JPS10 subwoofer. Can anyone identify this component for me, or point me to the schematic? It's a grey plastic rectangular capacitor, apparently without identifying marks. Two similar components are labeled 63V, .18J and 1J88 respectively. All these are on the smaller component board, which seems to be an active cross-over.

many thanks

Martin