Dodge Durango
 Service Manual
Heating and Air Conditioning » Description and operation
Vacuum check valve


Two vacuum check valves are installed in the accessory vacuum supply line in the engine compartment.

One check valve is located near the vacuum fitting on the power brake booster. The second check valve is located at the heater and air conditioner take-out of the accessory vacuum supply line. The vacuum check valves are designed to allow vacuum to flow in only one direction through the accessory vacuum supply circuits.


The use of the vacuum check valves help to maintain the system vacuum needed to retain the selected heater-A/C mode settings. The check valves will prevent the engine from bleeding down system vacuum through the intake manifold during extended heavy engine load (low engine vacuum) operation.

The vacuum check valves cannot be repaired and, if faulty or damaged, they must be individually replaced.

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    Dodge Durango Service Manual / Heating and Air Conditioning / Description and operation / Vacuum check valve

    Dodge Durango Service Manual


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