Leaving the battery connected while you're wiring in new electronics can result in damage to either the new device or other equipment in your car, so it's a good idea to just pull the negative battery cable.
Ịhapụ batrị ejikọrọ mgbe ị na-agbanye ọkụ na teknụzụ ọhụrụ nwere ike imebi ma ọ bụ ngwaọrụ ọhụrụ ma ọ bụ ngwaọrụ ndị ọzọ na ụgbọ ala gị, yabụ ọ bụ ezi echiche ka ịmepụta eriri batrị na-adịghị mma.