OnOff Control Vacuum Switching Valve VISC System

The simple On-Off Vacuum Switching Valve (VSV) ISC system is controlled by signals from the ECU or directly by tail lamp and rear window defogger circuits. The Vacuum Switching Valve (VSV) is typically located on the engine (often under the intake manifold) or in the engine compartment, controlling a fixed air bleed into the intake manifold.

The valve is a normally closed (N/Q design which is opened when current is passed through the solenoid windings. Unlike most ECU controlled circuits which are ground circuit driven, the ECU controls this VSV by supplying current to the solenoid coil when pre-programmed conditions are met. Additionally, current can be supplied to the solenoid from the rear window defogger or taillight circuits by passing through isolation diodes.

Vacuum Switch Valve Corolla

The VSV allows only a small amount of air to by-pass the closed throttle valve when it is open, increasing engine speed by about 100 rpm when energized. This ISC system does not control cold fast idle, and engines equipped with the system use a mechanical air valve for cold engine fast idle.

On-Off VSV ISC System Applications and Control Parameters

ISC Type/ Engine

Relevant Inputs

Controlled Parameters

On-Off Control VSV Type

Engine speed (Ne) Coolant temp. (THW) Air conditioner clutch (A/C)

• Engine Starting Stabilization

• 4A-GE

Electrical load (ELS)

• Air Conditioner Idle-up

• 3E-E

Throttle signal (IDL)

• 4Y-E

Vehicle speed (SPD)

• Electrical Load Idle-up

• 2S-E

Neutral switch (NSW)

• 3S-GE

• Automatic Transmission Idle-up

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Responses

  • tito
    What vacuum switching valve air cond?
    3 years ago
  • MARCO
    What is use of vsv valv?
    2 years ago
  • marja
    How does vacuum switch valve work?
    2 years ago
  • haylom kifle
    How to wire ac vacuum switching valve?
    1 year ago
  • sara
    What does a vacuum switching valve do on a toyota 4 runner 2006?
    8 months ago
  • cyrus
    What is the purpose of the vacuum switching valve on an engine?
    8 months ago
  • CASSIDY
    What does the vacuum switch in prius do?
    8 months ago
  • bellina
    What does visc car wireing?
    7 months ago
  • ARWEN
    WHY CHANGE OVER VACUUM VALVE ASSY IN 2017 CAMRY?
    7 months ago
  • WARREN
    Where is the vsv valve located on toyota rav4 mk3 diesel?
    7 months ago
  • Amanda
    Where is the vacuum valve located on a2012 toyota camry?
    7 months ago
  • fosco
    WHY TOYOTA PUT VACCUM SWITCHING VALVE ON ENGINE MOUNT?
    6 months ago
  • Ralph Kaufmann
    Where is the vacuum switching solenoid valve located on 2000 toyota avalon?
    6 months ago
  • ferdinanda
    Why does toyota use switching valves?
    6 months ago
  • rufus
    How does toyota 4aage vacuum switching valve work?
    4 months ago
  • kerstin
    How is vacuum switch valve toyota sienna 2002 work?
    3 months ago
  • james
    How to test vacuum actuator on 2000 toyota camry v6?
    3 months ago
  • olli-pekka
    How to control vacuum with valve?
    3 months ago
  • LAVINIA GRUBB
    Does a vacuum switch send vacuum to acutator?
    3 months ago
  • marilyn
    What closes vacuum on vsv valve on 2000 toyota camry v6?
    3 months ago
  • myla
    What does the engine contol system control on a toyota corolla?
    3 months ago
  • jennifer
    Where is the vacuum switch located on a 2001 toyota corolla ce?
    3 months ago
  • JANINA HOFFMANN
    How does vacume switching valve work?
    1 month ago
  • paavo
    What is the purpose of toyota sienna vacum switch?
    30 days ago
  • Rocco
    Where is vacuum switching value located on 2002 camry?
    28 days ago
  • Simret Nasih
    How to change a 9091012264 purge valve 2002 toyota?
    21 days ago
  • Paulina
    Where is the vacum switching valve on 2000 Tacoma?
    13 days ago
  • Muhammed
    How to install Vacuum switching valve #2 on 1995 Toyota 4RunnerV6 ?
    8 days ago
  • nuguse nasih
    Does the toyota rav4 diesel fuel cap operate with vacuum?
    7 days ago

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