ECM
Test requirements:
- Fuses for engine electronics OK
- Fuel Pump (FP) Relay OK
- Ground connections [1][2]Description of On-Board Diagnostics
Triggering sequence:
- Fuel Pump (FP) relay -J17-
- Idle Air Control (IAC) valve -N71-
- Intake manifold change-over valve -N156-
- EVAP canister purge regulator valve -N80-
- EGR vacuum regulator solenoid valve -N18-
- Secondary Air Injection (AIR) solenoid valve -N112- (only on vehicles with secondary air system)
- Secondary Air Injection (AIR) pump relay -J299- (only on vehicles with secondary air system)
NOTE:
- The output diagnostic test mode can only be carried out with the ignition switched on and the engine NOT running.
- The output diagnostic test mode is interrupted if the engine is started or a rotary pulse is recognized.
- During the output diagnostic test mode, the individual outputs are triggered until the program is continued by pressing the -> button.
- The outputs are checked by listening for the sound of the component being actuated, of by feeling for mechanical evidence of actuation (clicking, vibration, etc.).
- Without letting the engine run briefly, switch the ignition off for approx. 20 sec. before repeating the output diagnostic test mode.
- Connect VAG 1551 scan tool and initiate until "Select function" is indicated on the display.
Indicated on display
Rapid data transfer HELP
Select function XX
NOTE: After pressing the HELP button, an overview of the possible functions is printed out.
- Press buttons -0- and -3- to select "Output Diagnostic Test Mode" function 03.
Indicated on display
Rapid data transfer Q
03 - Output Diagnostic Test Mode
- Press -Q- button to confirm input.
Indicated on display
Output diagnostic test mode ->
Fuel Pump (FP) Relay -J17
The fuel pump relay must be triggers and the fuel pump must run; the flowing noise at the fuel pressure regulator can be clearly heard.
- If fuel pump relay is not triggered, check control, Testing and Inspection
- Press -> button.
Indicated on display
Output diagnostic test mode ->
Idle Air control (AC) valve -N71
This valve is triggered (clicks) until moving on to the next output by pressing the button.
- If the valve is not triggered (does not click), check -N71-, Testing and Inspection
- Press -> button.
Indicated on display
Output diagnostic test mode ->
Intake manifold change-over valve -N156
This valve is triggered (clicks) until you move on to the next output by pressing the -> button.
- If the valve is not triggered (does not click), check intake manifold change-over valve -N156- Testing and Inspection
- Press -> button.
Indicated on display
Output diagnostic test mode ->
Evaporative Emission (EVAP) canister
purge regulator valve -N80
This valve is triggered (clicks) until you move on to the next output by pressing the -> button.
- If the valve is not triggered (does not click), check EVAP canister purge regulator valve -N80- Testing and Inspection
- Press -> button.
Indicated on display
Output diagnostic test mode ->
EGR vacuum regulator solenoid valve -N18
This valve is triggered (clicks) until you move on to the next output by pressing the -> button.
- If the valve is not triggered (does not click), check EGR vacuum regulator solenoid valve -N18- Testing and Inspection
Only on vehicles with secondary air injection (AIR) system
Indicated on display
Output diagnostic test mode ->
Secondary Air Injection (AIR) solenoid valve -N112
This valve is triggered (clicks) until you move on to the next output by pressing the -> button.
- If the valve is not triggered (does not click), check -N112-.
Indicated on display
Output diagnostic test mode ->
Secondary Air Injection (AIR) pump relay -J299
The secondary air injection pump relay -J299- triggers the secondary air pump motor and it runs until the output DTM is ended by pushing the -> button (maximum 10 sec.).
- If secondary air injection pump motor does not run, check engine and -J299-.
- Press -> button.
Indicated on display
Rapid data transfer HELP
Select function XX
NOTE: Before selecting "Output Diagnostic Test Mode" function 03 again, switch ignition off for approx. 20 sec.