Audi AMB Service Manual page 300

ENGINE 1.8 Liter 4-Cyl. 5V Turbo Engine Mechanical, Engine Code(s): AMB
Fig. 390: Identifying Secondary Air Injection (AIR) Solenoid Valve -N112-
Courtesy of VOLKSWAGEN UNITED STATES, INC.
Disconnect connector at Secondary Air Injection (AIR) solenoid valve N112 - 2 -.
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Fig. 391: Connecting Multimeter To Valve (Resistance Measurement Range)
Courtesy of VOLKSWAGEN UNITED STATES, INC.
Connect multimeter and measure resistance at valve.
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Specification: 27 to 30 ohms
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If reading does not match specification:
Replace Secondary Air Injection (AIR) solenoid valve N112.
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If measured value matches specification:
Check power supply.
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Checking power supply
NOTE:
Secondary Air Injection (AIR) solenoid valve N112 is supplied with power
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2005 Audi A4 Quattro
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