Output Diagnostic Test Mode
Output Diagnostic Test Mode
• The Output Diagnostic Test Mode (DTM) can only be performed with the engine stopped and the ignition switched on.
• During actuator diagnosis, the individual actuators (with the exception of the injectors) are operated in turn for about one minute unless the next actuator is selected by pressing the > button.
• The control elements can be checked acoustically or by way of touch.
• The Output Diagnostic Test Mode (DTM) is terminated, if after 1 minute actuation time the next control element is not switched to, or the engine is started or an engine speed pulse is detected.
• Before restarting the Output Diagnostic Test Mode (DTM) the engine must be started and the ignition switched off and on again.
The Output Diagnostic Test Mode (DTM) activates the following components in the stated order:
* Only on vehicles with automatic transmission.
Requirements
• Fuses for engine electronics OK. Refer to
Work sequence
- Connect vehicle diagnostic, testing and information system (VAS 5051) and select vehicle system "01 - Engine electronics" in selection list. Ignition must be switched on.
Display on (VAS 5051):
- Under - 1 - select diagnostic function "03 - Output Diagnostic Test Mode (DTM)".
Activating Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80)
Display on (VAS 5051):
A - control element test running advance necessary
1. Evaporative Emission (EVAP) Canister Purge Regulator (N80)
- Press > button.
Display on (VAS 5051):
A - control element test running advance permitted
• This valve is activated (clicks) for approx. 1 minute if the operation is not switched to the next control element by pressing the > button.
• Fuel pump must run during actuation time, the flow noise at fuel pressure regulator must be clearly audible If fuel pump does not run, check activation:
• AWD.
If the valve is not activated (does not click).
- Check Evaporative Emission (EVAP) Canister Purge Regulator (N80) => [ , checking ] Testing and Inspection.
Activating Secondary Air Injection (AIR) solenoid valve (N112)
- Press > button.
Display on (VAS 5051):
A - control element test waiting advance necessary
2 Secondary Air Injection (AIR) Solenoid Valve (N112)
- Press > button.
Display on (VAS 5051):
A - control element test running advance permitted
• This valve (-Pos. 2- under intake manifold) is activated (clicks) for approx. 1 minute if the operation is not switched to the next control element by pressing the > button.
• The fuel pump must run during the activation time.
If the valve is not activated (does not click).
- Check Secondary Air Injection (AIR) Solenoid Valve (N112).
Activating Secondary Air Injection (AIR) Pump Relay (J299)
- Press > button.
Display on (VAS 5051):
A - control element test running advance permitted
3 Secondary Air Injection (AIR) Pump Relay (J299)
- Press > button.
Display on (VAS 5051):
A - control element test running advance permitted
• The Secondary Air Injection (AIR) Pump Relay (J299 ) (in relay carrier in electronics box, plenum chamber, position 3) switches the engine for the Secondary Air Injection (AIR) Pump Motor (V101) on and off at approx. 1 minute intervals if the operation has not been switched to the next control element by pressing the > button.
• The fuel pump must run during the activation time.
If secondary air pump does not run intermittently:
- Check Secondary Air Injection (AIR) Pump Relay ( J299).
Activating Wastegate Bypass Regulator Valve (N75)
- Press > button.
Display on (VAS 5051):
A - control element test running advance permitted
4 Wastegate Bypass Regulator Valve (N75)
- Press > button.
Display on (VAS 5051):
A - control element test running advance permitted
• This valve is activated (clicks) for approx. 1 minute if the operation is not switched to the next control element by pressing the > button.
• The fuel pump must run during the activation time.
If the valve is not activated (does not click).
Refer to => Fuel Delivery and Air Induction Fuel Delivery and Air Induction
Activating camshaft adjustment valves
- Press > button.
Display on (VAS 5051):
A - control element test waiting advance necessary
5 Camshaft timing control
- Press > button.
Display on (VAS 5051):
A - control element test running advance permitted
• This valve is activated (clicks) for approx. 1 minute if the operation is not switched to the next control element by pressing the > button.
• The fuel pump must run during the activation time.
If the valve is not activated (does not click).
- Check camshaft adjustment valves.
Activating Leak Detection Pump (LDP) ( V144)
- Press >-button.
Display on (VAS 5051):
A - control element test waiting advance necessary
6 Leak Detection Pump (LDP) ( V144) tank ventilation system
- Press >-button again.
Display on (VAS 5051):
A - control element test running advance permitted
• Leak Detection Pump (LDP) (V144) is activated (clicks) in intervals for approx. 1 minute, unless the >-button is pressed to switch to the next actuator.
• Operating noise of Leak Detection Pump (LDP) is softly audible at left rear wheelhouse.
If Leak Detection Pump (LDP) for tank ventilation system is not activated (no operating noise is audible):
- Check Leak Detection Pump (LDP) for tank ventilation system.
Activating Recirculating valve for turbocharger (N249)
- Press > button.
Display on (VAS 5051):
A - control element test waiting advance necessary
7 Recirculating valve for turbocharger (N249)
- Press > button.
Display on (VAS 5051):
A - control element test running advance permitted
• This valve (-Pos. 1- under intake manifold) is activated (clicks) for approx. 1 minute if the operation is not switched to the next control element by pressing the > button.
• The fuel pump must run during the activation time.
If the valve is not activated (does not click).
Refer to => Fuel Delivery and Air Induction Fuel Delivery and Air Induction
Activating brake vacuum pump *
* Only on vehicles with automatic transmission.
- Press > button.
Display on (VAS 5051):
A - Control element test waiting advance necessary
8 Activation of brake vacuum pump
- Press > button.
Display on (VAS 5051):
A - control element test running advance permitted
• The brake servo vacuum pump, front left in engine compartment, must start up for a short time, unless the operation has been switched to the next control element by pressing the > button.
If the brake servo vacuum pump does not start up:
- Check brake servo vacuum pump.
Activating Coolant Fan Control (FC) control module (J293)
- Press > button.
Display on (VAS 5051):
A - control element test waiting advance necessary
9 Coolant Fan activation
- Press > button.
Display on (VAS 5051):
A - control element test running advance permitted
• The Coolant Fan Control 1 (J293) (top right on radiator cowl - arrow -) switches the coolant fan on once slowly to full speed, if the operation has not been switched to the next control element by pressing the > button.
• The fuel pump must run during the actuation time.
If the fan does not start:
- Check coolant fan and Coolant Fan Control 1 ( J293).
Activating fuel injectors
• Fuel injectors are activated according to ignition sequence: Cyl. 1, Cyl. 3, Cyl 4, Cyl. 2.
- Press > button
Display on (VAS 5051):
A - control element test waiting advance necessary
10 - Cylinder 1 fuel injector (N30)
- Press > button again.
Display on (VAS 5051):
A - control element test running advance permitted
• Fuel injector must click 5 times after > button is pressed.
• Fuel pump must run during activation time.
- Press > button
Display on (VAS 5051):
A - control element test waiting advance necessary
11 - Cylinder 3 Fuel Injector (N32)
- Press > button again.
Display on (VAS 5051):
A - control element test running advance permitted
• Fuel injector must click 5 times after > button is pressed.
• Fuel pump must run during activation time.
- Press > button
Display on (VAS 5051):
A - control element test waiting advance necessary
12 - Cylinder 4 Fuel Injector (N33)
- Press > button again.
Display on (VAS 5051):
A - control element test running advance permitted
• Fuel injector must click 5 times after > button is pressed.
• Fuel pump must run during activation time.
- Press > button
Display on (VAS 5051):
A - control element test waiting advance necessary
13 - Cylinder 2 Fuel Injector (N31)
- Press > button again.
Display on (VAS 5051):
A - control element test running advance permitted
• Fuel injector must click 5 times after > button is pressed.
• Fuel pump must run during activation time.
If one of the fuel injectors is not activated (does not click).
- Check fuel injectors. Refer to => [ Fuel Injectors, Checking ] Fuel Injectors, Checking.
- Press > button
Display on (VAS 5051):
A - Actuator test has ended
- End function "03 - output Diagnostic Test Mode (DTM)" by pressing arrow button.
• Before re-initiating output Diagnostic Test Mode (DTM), engine must be started and the ignition must be switched off and on again.