P1436

DTC P1436 Bypass Valve Malfunction

CIRCUIT DESCRIPTION

DTC Detecting Condition:

Before the engine is started, the bypass valve remains open. When the engine is cold started, the ECM outputs a signal to the VSV (for HC adsorber and catalyst system), which open the passage between the intake manifold and the actuator, thus applying a vacuum to the actuator. As a result, the bypass valve closes. Immediately after the engine has started, the exhaust gases pass through the adsorber material in with HC becomes adsorbed and stored for a certain length of time (until the temperature of the front TWC rises). Thus, the release of HC into the atmosphere is prevented when the temperature of the TWC is low. After the TWC has warmed up, the VSV closes the passage between the intake manifold and the actuator, causing the bypass valve to open. Then, as the temperature of the rear TWC rises, the temperature of the adsorber material that surrounds it also rises, and the HC starts to desorb, and becomes cleaned by the TWC.

Furthermore, this system activates the VSV when decelerating and the HC adsorber has become the specified temperature, allowing the vacuum from the intake manifold to close the bypass valve in order to scavenge the HC that remains in the adsorber material.

Step 1 - 2:

Step 3 - 6:

INSPECTION PROCEDURE