Audi Q7: Secondary Air Injection Pump Relay - J299- / Secondary Air Injection Pump
Motor - V101-, Checking
General Description
The secondary air injection system sends air into the
exhaust using passages in the cylinder head. This extra air
injection takes place using the Secondary Air Injection Pump
Motor -V101- that is powered by the Secondary Air Injection Pump
Relay -J299- on a cold-start of the engine for about 45 - 100 s
and serves to quickly heat the catalytic converter(s) for
improved emissions.
Special tools and workshop equipment
required
- Multimeter.
- Wiring Diagram.
- Scan Tool.
Test requirements
- Fuses OK.
- Battery voltage OK.
- Switch OFF all electrical and electronic accessories.
- Vehicles with automatic transmission, ensure the selector
lever position is in "P".
- Vehicles with manual transmission, ensure the shifter lever
position is in "N" with the parking brake applied.
- Coolant temperature: ≥ 80º C.
- Observe all safety precautions:
→ Chapter "Safety Precautions".
- View clean working conditions:
→ Chapter "Clean Working Conditions".
- For Hybrid vehicles, refer to:
→ Chapter "High Voltage System General Warnings".
Test Procedure
Secondary Air Injection Solenoid Valve - N112-, Checking
General Description
The secondary air injection system sends air into the
exhaust, behind the exhaust valves, using a passage in the
cylinder head. This extra air injection takes place on a
cold-start of the engine for about 45 - 100 s and serves to
quickly heat the catalytic converter(s) for improved emissions.
A "pressure based secondary air diagnostics" function is used.
In this system, the Engine Control Module -J623- controls the
Secondary Air Injection Solenoid Valve -N112-, which allows the
correct amount of air to be injected. The injected air quantity
is determined from the pressure level.
Special tools and workshop equipment
required
- Multimeter.
- Wiring Diagram.
- Scan Tool.
Test requirements
- Fuses OK.
- Battery voltage OK.
- Switch OFF all electrical and electronic accessories.
- Vehicles with automatic transmission, ensure the selector
lever position is in "P".
- Vehicles with manual transmission, ensure the shifter lever
position is in "N" with the parking brake applied.
- Coolant temperature: ≥ 80º C.
- Observe all safety precautions:
→ Chapter "Safety Precautions".
- View clean working conditions:
→ Chapter "Clean Working Conditions".
- For Hybrid vehicles, refer to:
→ Chapter "High Voltage System General Warnings".
Test Procedure
Three Way Catalytic Converter (TWC), Checking
General Description
A catalytic converter is a vehicle emissions control device
that converts toxic pollutants in exhaust gas to less toxic
pollutants by catalyzing a redox reaction (oxidation or
reduction). Catalytic converters are used in internal combustion
engines.
General recommendations
Oxygen sensors OK.
No leaks or damage to exhaust system.
Prior to repair work, perform a preliminary check to verify
the condition. Refer to
→ Chapter "Preliminary Check".
Test requirements
- Fuses OK.
- Battery voltage OK.
- Switch OFF all electrical and electronic accessories.
- Vehicles with automatic transmission, ensure the selector
lever position is in "P".
- Vehicles with manual transmission, ensure the shifter lever
position is in "N" with the parking brake applied.
- Coolant temperature: ≥ 80º C.
- Observe all safety precautions:
→ Chapter "Safety Precautions".
- View clean working conditions:
→ Chapter "Clean Working Conditions".
- For Hybrid vehicles, refer to:
→ Chapter "High Voltage System General Warnings".
Function test
Throttle Valve Control Module - GX3-, Checking
General Description
Throttle valve operation occurs by an electric motor
identified as the EPC Throttle Drive -G186- located within the
Throttle Valve Control Module -GX3-. It is controlled by the
Engine Control Module - J623- with primary inputs from the
Accelerator Pedal Module -GX2- as well as other peripheral
inputs from the EPC Throttle Drive Angle Sensor 1 -G187- and the
EPC Throttle Drive Angle Sensor 2 -G188-.
Note the Throttle Valve Control Module - GX3- is also
referred to as the Throttle Valve Control Module -J338-.
The Throttle Valve Control Module -GX3 / J338- contains the
following components:
- Throttle Valve Control Module -J338-
- EPC Throttle Drive -G186-
- EPC Throttle Drive Angle Sensor 1 -G187-
- EPC Throttle Drive Angle Sensor 2 -G188-
The Throttle Valve Control Module -GX3 / J338- components
cannot be serviced separately, and they must be serviced as a
unit.
Special tools and workshop equipment
required
- Multimeter.
- Wiring Diagram.
- Scan Tool.
Test requirements
- Fuses OK.
- Battery voltage OK.
- Switch OFF all electrical and electronic accessories.
- Vehicles with automatic transmission, ensure the selector
lever position is in "P".
- Vehicles with manual transmission, ensure the shifter lever
position is in "N" with the parking brake applied.
- Coolant temperature: ≥ 80º C.
- Observe all safety precautions:
→ Chapter "Safety Precautions".
- View clean working conditions:
→ Chapter "Clean Working Conditions".
- For Hybrid vehicles, refer to:
→ Chapter "High Voltage System General Warnings".
Test Procedure
Turbocharger Speed Sensor 1 - G688-, Checking
General Description
The supercharger speed sensor detects the speed of the
mechanically driven supercharger and transmits this information
to the Engine Control Module -J623-.
Special tools and workshop equipment
required
- Multimeter.
- Wiring Diagram.
- Scan Tool.
Test requirements
- Fuses OK.
- Battery voltage OK.
- Switch OFF all electrical and electronic accessories.
- Vehicles with automatic transmission, ensure the selector
lever position is in "P".
- Vehicles with manual transmission, ensure the shifter lever
position is in "N" with the parking brake applied.
- Coolant temperature: ≥ 80º C.
- Observe all safety precautions:
→ Chapter "Safety Precautions".
- View clean working conditions:
→ Chapter "Clean Working Conditions".
- For Hybrid vehicles, refer to:
→ Chapter "High Voltage System General Warnings".
Test Procedure
Vehicle Speed Signal, Checking
General Description
The Vehicle Speed Signal or VSS measures Transmission /
Transaxle output or Wheel Speed from the ABS. The signal is
broad casted over the CAN Bus. The Engine Control Module -J623-
uses this information to modify engine functions such as
ignition timing, A/F ratio, transmission shift points, and to
initiate diagnostic routines.
Special tools and workshop equipment
required
- Multimeter.
- Wiring Diagram.
- Scan Tool.
Test requirements
- Fuses OK.
- Battery voltage OK.
- Switch OFF all electrical and electronic accessories.
- Vehicles with automatic transmission, ensure the selector
lever position is in "P".
- Vehicles with manual transmission, ensure the shifter lever
position is in "N" with the parking brake applied.
- Coolant temperature: ≥ 80º C.
- Observe all safety precautions:
→ Chapter "Safety Precautions".
- View clean working conditions:
→ Chapter "Clean Working Conditions".
- For Hybrid vehicles, refer to:
→ Chapter "High Voltage System General Warnings".
Test Procedure
READ NEXT:
Identification
Engine Number/Engine Specifications
Engine Number
Note
The engine number can only be seen with the engine cover
removed.
The engine number ("engine code" and "serial number")
SEE MORE:
Overview - Fender
1 - Double Bolt
10 Nm
Quantity: 3
2 - Fender Brace
Removing and Installing. Refer to
→ Chapter "Fender Brace, Removing and Installing".
3 - Bolt
10 Nm
Quantity: 4
4 - Bolt
10 Nm
5 - Center Bracket
Removing
Applies to: vehicles with adaptive cruise control
Fig. 112 Operating lever: setting the distance
When approaching a vehicle driving ahead, the
adaptive cruise control system brakes to match
that vehicle's speed and then adjusts to the set
distance. If the vehicle driving ahead accelerates,
then th