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So my question is if booster is leaking pressure will the headlight work or does it have its own presure vacuum
The booster is separate....but a vacuum leak there can cause overall vacuum that the engine provides to decrease..which decreases available vacuum to all systems...the lights may or may not work depending on the extent of the leak.
If you are trying to determine if you have a leaky diaphragm....put a pair of Vice Grips or similar clamp and choke off the supply hose to the booster while running......if your engine idle changes.....you may very well have a bad booster.