Output Diagnostic Test Mode

Output Diagnostic Test Mode (DTM) (Function 03)

NOTE:
- The Output Diagnostic Test Mode (DTM) can be performed more than once if necessary.
- Malfunctions in final control elements checked during the output DTM are stored as DTCs in DTC memory.
- Checking the Idle Air Control (IAC) regulation function.
IAC Regulation, Initiating Output Diagnostic Test Mode (DTM)

- During output DTM, the vehicle must not be moved and the engine speed must be lower than 3000 RPM.
- During output DTM, the air conditioning control functions are switched off and all segments of the A/C Control Head -E87- displays are activated.

Initiating output DTM
- Start engine.
- Press AUTO button to switch compressor on.
- Open instrument panel vents.
- Set air distribution to instrument panel vents.
- Connect VAG 1551 Scan Tool (ST).
Scan Tool Connecting and Initial Checks

- Press buttons -0- and -8- to insert "AC/Heating Electronics" address word 08 and advance program until "Select function XX" appears on display.
Scan Tool Connecting and Initial Checks

- Switch printer on by pressing PRINT button (indicator lamp in button comes on).
- Check DTC memory.

Indicated on display


Rapid data transfer HELP
Select function XX


- 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 ->
A/C Clutch-N25


NOTE:
- The -> button is used to advance through the program sequence.
- Output diagnostic test mode can be stopped by pressing the -C- button.
- When output diagnostic test mode has been completed, check DTC memory.
- If, at the beginning of output diagnostic test mode the message "Function is unknown or cannot be carried out at the moment" appears on the display (e.g. if the engine is not running), press the -> button and select function 03 (output diagnostic test mode) again. (The control element "A/C clutch-N25" will no longer be activated during this test.)
- If the message "Function is unknown or cannot be carried out at the moment" appears on the display, refer to Read Measuring Value Block (display group 001).
Evaluating Display Group 001

Indicated on display


Function is unknown or ->
cannot be carried out at the moment


If this readout is displayed, the output DTM is ended.
- Press -> button.