Dodge Durango

 Service Manual

Speed Control System » Description and operation
Vacuum reservoir

DESCRIPTION

The vacuum reservoir is a plastic storage tank connected to an engine vacuum source by vacuum lines.

OPERATION

The vacuum reservoir is used to supply the vacuum needed to maintain proper speed control operation when engine vacuum drops, such as in climbing a grade while driving. A one-way check valve is used in the vacuum line between the reservoir and the vacuum source. This check valve is used to trap engine vacuum in the reservoir. On certain vehicle applications, this reservoir is shared with the heating/ air-conditioning system. The vacuum reservoir cannot be repaired and must be replaced if faulty.

Speed control system

Speed control servo

Speed control solenoid circuits

Speed control switches

Brake lamp switch

Servo cable

Vacuum reservoir

Vehicle speed input