Repair manual

SULEV 2.0L TFSI Engine
29
Secondary Air Injection Sensor 1 G609
Secondary Air Injection Sensor 1 G609 connects to
the pressure line coupling upstream of Secondary Air
Injection Valve N112. It supplies the ECM with an analog
output signal of between 0.5 and 4.5 V.
Its measurement window is between 7 and 22 psi
(50 kPa – 150 kPa).
Signal Utilization
This signal is used for diagnosing the secondary air
system. Because the system is relevant to exhaust
emissions, legislation requires that it be monitored.
Effects of Signal Failure
A diagnosis is made for the sensor and used to monitor
voltage (min-max threshold), and to match ambient
pressure and the secondary air pressure sensor (phase 0).
If a fault occurs in a sensor, the system diagnosis result
will not be evaluated because the sensor signal will be
implausible. However, a diagnosis will still be made.
Diagnostics
If Secondary Air Injection Valve N112 remains closed due
to a malfunction, the resulting pressure will be too high.
Conversely, the pressure will be too low if a leak occurs in
the system upstream of the secondary air injection valve.
In both cases, the corresponding fault memory entries
are saved to the ECM, and Malfunction Indicator Lamp
(MIL) K83 is activated.
Signal Output Voltage U
A
[V]
Absolute Pressure p
abs
psi (kPa)
Signal Characteristic of the Secondary Air Pressure Sensor
6.0 (40)
7.2 (50) 8.7 (60) 10.1 (70) 11.6 (80) 13.0 (90) 14.5 (100) 15.9 (110)
17.4 (120)
18.8 (130)
20.3 (140)
21.7 (150) 23.2 (160) 24.6 (170)
5.00
4.50
4.00
3.50
3.00
2.50
2.00
1.50
1.00
0.50