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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  • tito
    What vacuum switching valve air cond?
    3 years ago
    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?
    1 year ago
  • cyrus
    What is the purpose of the vacuum switching valve on an engine?
    1 year ago
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    12 months ago
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    What does visc car wireing?
    11 months ago
    11 months ago
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  • Amanda
    Where is the vacuum valve located on a2012 toyota camry?
    11 months ago
  • fosco
    10 months ago
  • Ralph Kaufmann
    Where is the vacuum switching solenoid valve located on 2000 toyota avalon?
    10 months ago
  • ferdinanda
    Why does toyota use switching valves?
    10 months ago
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    How does toyota 4aage vacuum switching valve work?
    8 months ago
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    How is vacuum switch valve toyota sienna 2002 work?
    7 months ago
  • james
    How to test vacuum actuator on 2000 toyota camry v6?
    7 months ago
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    How to control vacuum with valve?
    7 months ago
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    7 months ago
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    What closes vacuum on vsv valve on 2000 toyota camry v6?
    7 months ago
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    What does the engine contol system control on a toyota corolla?
    7 months ago
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    Where is the vacuum switch located on a 2001 toyota corolla ce?
    7 months ago
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    5 months ago
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    What is the purpose of toyota sienna vacum switch?
    5 months ago
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    Where is vacuum switching value located on 2002 camry?
    5 months ago
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    How to change a 9091012264 purge valve 2002 toyota?
    5 months ago
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    Where is the vacum switching valve on 2000 Tacoma?
    4 months ago
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    How to install Vacuum switching valve #2 on 1995 Toyota 4RunnerV6 ?
    4 months ago
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    Does the toyota rav4 diesel fuel cap operate with vacuum?
    4 months ago
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    What is a vsv on mr2 mk1?
    4 months ago
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    Where arae the 3 2012 avalon vacuum solinoids?
    3 months ago
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    Why is that for vacuum swich system for toyota 4 runner?
    3 months ago
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    How does the vacuum switching valve work on 1996 land cruiser?
    2 months ago
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    What is switching vacuum purge valve?
    1 month ago
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    How long does it take to replace vacuum switching valve toyota avalon 2002?
    1 month ago
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    Can a vacuum switching valve damage motor mounts?
    1 month ago
  • santina greco
    What do the VALVE ASSEMBLY, VACUUM SWITCHING, NO. 2 control?
    22 days ago
  • sisko tompuri
    What does the ac control solenoid valve toyota?
    12 days ago

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