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Headlight test

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Old Jul 9, 2011 | 12:20 PM
  #1  
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Default Headlight test

Hey Gang,
Assembling front grill area components and really don't want to remove it all again to repair headlights IF they malfunction, is there an easy way to test the vacuum cans? (note word EASY).

Steve
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Old Jul 9, 2011 | 12:32 PM
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2019 C3 of Year Finalist (appearance mods)
Default Headlight Troubleshooting

Actuator test: http://www.corvette-101.com/vacuum.htm#actuator

Have a helper hold the hood 100% up and the actuators will come out from the top.
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Old Jul 9, 2011 | 12:37 PM
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Hi Z,
The actuators can be tested with a vacuum pump and gauge.
Disconnect the green hose and hook the red hose to the pump. If vacuum holds, the internal diaphram is good.
Disconnect the red hose and hook the green hose to the pump. If the vacuum holds the internal diaphram and rear sealing grommet are good.
Check the relay valve while you're there too.
Good Luck!
Regards,
Alan
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Old Jul 9, 2011 | 01:37 PM
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With the car running just pinch the small hose at the intake manifold! The one from the check valve. This will make the lights go up.
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Old Jul 9, 2011 | 01:40 PM
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I don't know what year you have.. but pinch it at C or you could use B.

If the car isn't running.. then you can use a might vac... on hose's 4 or 3


Last edited by Willcox Corvette; Jul 9, 2011 at 01:42 PM.
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Old Jul 9, 2011 | 05:01 PM
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Hi Alan,
car is getting close, thanks to all for the help.

Wilcox, car is not "runnable" yet I'll need to go get a vacuum pump. Thanks for the schematic, that will really help me later.

Steve
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Old Jul 9, 2011 | 06:01 PM
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Here's a link that does a good job of explaining how thw vacuum headlights work.

http://forums.corvetteforum.com/c3-t...tem-works.html

Scott

You just lost the game!!!
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