Operation CHARM: Car repair manuals for everyone.

With Manufacturer's Scan Tool




Secondary air valve, checking

Special tools, equipment, test and inspection devices; required accessories





- VAG 1594 A auxiliary measuring tool set





- VAG 1527 B diode test lamp

Test condition
- Coolant temperature 5 - 33°C
- Air pump motor OK.

Test sequence





- Pull upper vacuum hose -arrow- of secondary air valve.
- Start motor and let it idle.
If the motor starts, it will be possible to feel a vacuum at the secondary air valve inlet nozzles.
If no vacuum can be detected:
- Switch ignition off.
- Remove 2-pin connector from secondary air valve -1-.





- Connect VAG 1527 diode test lamp to disconnected attachment plug using auxiliary cables from VAG 1594.
If the LED illuminates (power supply OK):
- Turn off ignition.
- Replace secondary air valve -N112-.
If the LED does not illuminate:
- Clip on 2-terminal attachment plug.
- Start the control element diagnosis and trigger the secondary air valve N112-.
- Check DTC memory.
- Read-out readiness code.
- If fault memory was erased or engine control unit was separated from positive voltage supply, readiness code must be regenerated.