General information
All models equipped with AT are equipped with an electronic control system for adjusting the parameters of the rear support of the power unit. The controlled parameter is the vibration level of the unit at idle engine speed. Inside the support assembly are two chambers filled with working fluid. When the engine is idling, the powertrain control module (RSM), generates a command to turn on the solenoid valve installed on the rear bulkhead of the engine compartment, which controls the supply of vacuum from the inlet pipeline to the rear suspension support of the power unit. A change in the depth of vacuum supplied to the assembly leads to a redistribution of the working fluid between the internal chambers of the support, which makes it possible to significantly reduce the level of vibrations transmitted from the engine to the car body. When the engine speed rises above 1000 rpm, the vacuum supply is cut off and the support switches to a passive mode of operation, working as a normal cushion cushion.
Examination
1. When the vibration level increases with the transition to idle, check the vacuum hoses connected to the solenoid valve for controlling the functioning of the rear support of the suspension of the power unit for signs of leaks and mechanical damage.
2. With a warm engine running at idle (less than 800 rpm) ask an assistant to turn on the transmission (parking brake is cocked, foot - squeezed out). At this time, turn on and off the power supply to the solenoid valve several times (by disconnecting-connecting the wiring connector). If the valve is functioning properly, there should be a noticeable change in vibration level.
3. Move the transmission to "R" or "N", disconnect the wiring and check for battery voltage at the black/yellow wire terminal. If there is no voltage, check the condition of the circuit from the connector to fuse No. 6 in the mounting block located on the left under the instrument panel (see chapter Onboard electrical equipment).
4. Raise the engine speed to 1000 rpm - the voltage should disappear from the black-yellow wire terminal in the valve connector, otherwise check the electrical wiring going to the PCM for signs of a short circuit.
5. Measure the voltage between the terminals of the two wires of the connector. There should be battery voltage, otherwise check the condition of the circuit between the connector and the PCM.
6. Disconnect the upper vacuum hose from the solenoid valve and apply a vacuum to it with a depth of 228 mm Hg. Art. from a manual vacuum pump. The vacuum must be maintained for at least 20 seconds, otherwise the hose or the support assembly itself must be replaced.
7. Without turning off the engine, create and release vacuum several times - there should be a noticeable change in the intensity of vibrations.
8. Disconnect the lower vacuum hose from the solenoid valve and make sure that there is a vacuum in the inlet pipeline on it. If there is no vacuum, check the condition of the hose. In the presence of vacuum, but the absence of the required response to its supply (see paragraph 7), replace the valve.