Audi AMB Service Manual page 299

ENGINE 1.8 Liter 4-Cyl. 5V Turbo Engine Mechanical, Engine Code(s): AMB
Fig. 389: Connect Test Hose To Valve Connection
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Connect test hose to valve connection marked with an - arrow -.
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Start output Diagnostic Test Mode and actuate Secondary Air Injection (AIR) solenoid valve N112.
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Indicated on display
Output Diagnostic Test Mode -->
Secondary Air Injection solenoid valve -N112
Valve must click...
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..and must open and close (can be checked by blowing into test hose).
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If valve does not click:
Check internal resistance of valve.
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If valve does not open or close properly:
Replace Secondary Air Injection (AIR) solenoid valve N112.

Checking internal resistance
2005 Audi A4 Quattro
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