A protective enclosure for an electronic control unit (ECU) to minimize risk of environmental intrusion includes a base portion, a first housing, a second housing, a first gasket, a vibration attenuating insert, a first electrical connector, a second electrical connector, a third electrical connector, and a tether. The first housing is sealably assembled onto the base portion, and the first housing and the base portion define a first chamber to house the telematics module. The second housing and the base portion define a second chamber. The tether attaches the base portion and the second housing.