DME Self-Diagnosis

DME Self-Diagnosis:
Monitoring of signals by the DME control unit allows the system to perform reliable and precise diagnosis. It is also possible to activate certain additional functions such as the actuator test and switching input test using the Porsche System Tester 2 and to check that they are functioning correctly.

Reading out the fault memory and deleting the fault memory can be performed using the new Porsche System Tester 2. The diagnosis socket is installed underneath the knee protection bar on the driver's side.

Scope Of Diagnosis:
The following are monitored and, if a fault occurs, entered in the fault memory:

Table 1 Of 6:

Table 2 Of 6:

Table 3 Of 6:

Table 4 Of 6:

Table 5 Of 6:

Table 6 Of 6:

Additional Diagnosis Features (USA Vehicles):

Table 1 Of 2:

Table 2 Of 2:

As for the 911 Turbo, the Boxster is also subject to the regulations specified by the US emissions authority with regard to pollution limit values, emissions test in line with a predefined driving cycle (FTP 72), fault detection, and fault administration (if 1.5 times a defined pollutant limit value is registered, the check-engine lamp must be activated). These regulations are described in the model brochure for the 911 Turbo OBD II diagnosis.

Therefore, for the DME control unit for USA models, apart from the diagnosis functions already provided for FRG and ROW vehicles, all emission-related faults are indicated by the check-engine lamp (only combustion faults endangering the catalytic converters are indicated in the cave ROW and FRG variants) and the extra components are also monitored. In addition, the catalytic conversion and VarioCam adjustment of the camshaft for 4 - 6 must also be monitored.

Additional Functions:
Apart from the data already available at the DME control unit of the 911 Turbo and entered in the permanent memory of the control unit such as vehicle ID number, engine number, M numbers, operating hours counter, etc., the recorded maximum speed of the engine is also stored and updated in the Boxster's control unit.

The following actuators can be checked using the Porsche System Tester 2:
Passive (only ignition on):
Idle air control valve
Air-conditioning compressor
Tank venting valve
Engine compartment scavenging blower
Secondary air pump (USA)
Check engine
Engine fan, speed 1 + 2
Fuel pump relay
Speed signal pulse (e.g. engine speed sensor)

Active (engine running):
Deactivation of the injection valves
Switch for VarioCam system, cylinder 1 - 3
Switch for VarioCam system, cylinder 4 - 6

The following switching inputs can be checked using the Porsche System Tester 2:
Idle speed detection
Full-load detection
Switch for air-conditioning compress
Reference mark signal
Driving position switch (with Tiptronic)
Warning lamp for fuel reserve
Switch for start release (with manual transmission)

The following actual values can be checked using the Porsche System Tester 2:
Supply voltage in volts
Hot-film mass air flow sensor voltage in volts
Engine temperature in °C
Intake air temperature in °C
Engine compartment temperature in °C
Engine oil temperature in °C
Engine speed in rpm
Vehicle speed in miles or km/h
Load signal in ms/revolution
Throttle potentiometer in %
Air mass in kg/h
Nominal air mass in kg/h
Adaptation values, range 1 (TRA)
Adaptation values, range 2 (FRA)
Adaptation values during tank venting (FTEA)
Ignition angle in CS
Oxygen regulator
Oxygen sensor voltages before catalytic converter
Oxygen sensor voltages after catalytic converter (USA)
Ambient pressure in mbar
Signal from airbag control unit

The following can be read out in a separate "status menu":
OBD status
Ready code
Trip counter

Brief test:
The "Brief test" function already used in the 911 Turbo has been extended for the Boxster.
This means that the functions to satisfy the diagnosis condition "trip completed" (all diagnosis paths have been checked 1 x) can be performed using the Porsche System Tester 2 without the vehicle having to be driven.

Note:
The DME control module is protected against manipulation.

Control module data can be changed externally using the new Porsche System Tester 2 if certain conditions are fulfilled.