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Function of the Components



Control Unit Function (part 2)

Function Of The Components







Gateway
The gateway is integrated into the PCM2. Together with the MMI, it is a fixed component of each PCM2. It provides a connection to CAN Comfort via its nodes. Diagnosis and useful data is exchanged with CAN via these nodes.

It creates links to the following systems:
- CAN Comfort
- Media Oriented Systems Transport (MOST), internal (electrical)
- Voice control system (VOCS) (optional/insertion)
- Navigation (optional/rack)
- Man Machine Interface (MMI)
- Single CD
- Media Oriented Systems Transport (MOST), external bus (optical)
- Amplifier optional (Harman or BOSE)
- CD changer
- Telephone/telematics

Identification
The diagnosis software number and the part numbers for the PCM2 can be read out under this menu item.
1. Connect and start Porsche System Tester II No. 9588 and switch on the ignition.
2. Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
3. Select 'PCM' in the control modules selection and confirm with the >> key.
4. Select 'PCM2 MMI' in the 911 Turbo (996) PCM2 function selection menu and confirm with the >> key.
5. Select 'Identification' in the PCM2 MMI function selection and confirm with the >> key.
6. The message "Diagnosis software number; parts number PCM2" appears on the display
7. Call up the "Extended identification" menu item with the F8 key.

Actual Values
It is possible to read out the unlock counter under the 'Actual values' menu item.

Menu Item Function

- Date Using this menu item, you can read out the current date of the PCM2.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select 'PCM' in the control modules selection and confirm with the >> key.
- Select 'PCM2-MMI' in the 911 Turbo (996) function selection and confirm with the >> key.
- Select the Actual values menu item and press the >> key.
- Select "Date" in the PCM2-MMI actual values menu using the > key and press the >> key.
- Read out values from the display field.

- Transmission fault Using this menu item, you can read out the current time of the PCM2.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select 'PCM' in the control modules selection and confirm with the >> key.
- Select 'PCM2-MMI' in the 911 Turbo (996) function selection and confirm with the >> key.
- Select actual values menu item and confirm with the >> key.
- Select "Transmission fault" in the PCM2-MMI actual values menu with the > key and confirm with the >> key.
- Read out values from the display field.

- Time Using this menu item, you can read out the current time of the PCM2.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select 'PCM' in the control modules selection and confirm with the >> key.
- Select 'PCM2-MMI' in the 911 Turbo (996) function selection and confirm with the >> key.
- Select actual values menu item and confirm with the >> key.
- Select "Time" in the PCM2-MMI actual values menu with the > key and confirm with the >> key.
- Read out values from the display field.

- Unlock counter Using this menu item, you can read out the traffic announcement volume boost setting.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select 'PCM' in the control modules selection and confirm with the >> key.
- Select 'PCM2-MMI' in the 911 Turbo (996) PCM2 function selection and confirm with the >> key.
- Select 'Coding' in the PCM-MMI function selection menu and press the >> key.
- Select "Unlock counter" in the PCM2-MMI coding menu with the > key and confirm with the >> key.
- Read out values from the display field.

- Traffic announcement
volume boost Using this menu item, you can read out the traffic announcement volume boost setting.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select 'PCM' in the control modules selection and confirm with the >> key.
- Select 'PCM2-MMI' in the 911 Turbo (996) PCM2 function selection and confirm with the >> key.
- Select 'Coding' in the PCM-MMI function selection menu and press the >> key.
- Select "Traffic announcement volume boost" in the PCM2-MMI coding with the > key and confirm with the >> key.
- Read out values from the display field.

- Time zone Using this menu item, you can read out the current time zone of the PCM2.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select 'PCM' in the control modules selection and confirm with the >> key.
- Select 'PCM2-MMI' in the 911 Turbo (996) function selection and confirm with the >> key.
- Select 'Coding' in the PCM2-MMI menu and confirm with the >> key.
- Select "Time zone" in the PCM2-MMI coding menu with the > key and confirm with the >> key.
- Read out values from the display field.

Lock/Unlock
A lock occurs when the signal sent from the MMI via the wake-up/diagnosis distribution line is understood and answered by the connected MOST control modules; in this way a 'lock (connection)' is brought about. This is maintained until the signal is not received for a longer time 'unlock'.

Man Machine Interface (MMI)
The MMI is part of the PCM2 (on the mainboard). It runs the gateway commands via the wake-up signal line and the diagnosis of the distribution line.

MOST Actual Installations List/MOST Required Installations List
All MOST control modules that are connected to the PCM2 are entered in the 'required installations list'. An actual installations list is written and saved when the PCM2 is started.

MOST - Optical/Electrical
MOST signals are transferred electrically within the PCM2 and optically outside of the PCM2. Internally, the PCM2 consists of at least 2 nodes (GW and MMI), which are installed in the device and can also be expanded to four nodes by adding the navigation and VOCS nodes.

The data is transferred outside of the PCM2 via the optical waveguide, which creates a connection to the nodes in the external MOST control modules such as external amplifiers, CD changers and/or telephone/telematics (depending on the equipment). The gateway node represents the connection to CAN Comfort.

MOST Switch
The MOST switch is part of the PCM2. It keeps the electrical MOST closed if no other MOST control module is optically connected to the MOST. The MOST switch is opened when a light signal is received from the connected MOST control modules.

NOTE:
- When the PCM2 is replaced, the coding must be performed in accordance with the connected MOST control modules.
- When the 'Switch closed' parameter is set, the switch remains closed even in existing MOST control modules. Communication is then not possible.

Navigation
The navigation module is designed as a module box which can be pushed into the PCM2 (optional). After inserting, an electronic connector is automatically opened and the module is integrated into the MOST ring.

Drive Links
Drive links of the PCM2 can be activated with this menu item. This allows the function of the drive links to be assessed very quickly.

The following drive links can be controlled with the Porsche System Tester II No. 9588:
- Display colour black
- Display colour "colour bar"
- Display colour blue
- Display colour red
- Display colour green
- Display colour white
- Set default values
- Distribution breakage diagnosis
- Distribution breakage line diagnosis

NOTE: The activated drive link is automatically switched off after approximately 20 seconds.

Menu Item Function

- Display colour black Using this menu item, you can read out the current date of the PCM2.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select 'PCM' in the control modules selection and confirm with the >> key.
- Select 'PCM2-MMI' in the 911 Turbo (996) function selection and confirm with the >> key.
- Select 'Drive links' in the PCM2-MMI menu and press the >> key.
- Select "display colour black" in the PCM2-MMI drive links menu with the > key and confirm with the F8 key.
- The display must indicate the respective colour.

Proceed in the same way with the following tests.
- Display colour "colour bar."
- Display colour blue.
- Display colour red.
- Display colour green.
- Display colour white.

- Set default values. Using this menu item, you can read out the current time of the PCM2.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select 'PCM' in the control modules selection and confirm with the >> key.
- Select 'PCM2-MMI' in the 911 Turbo (996) function selection and confirm with the >> key.
- Select drive links menu item and confirm with the >> key.
- Select "Set default values" in the PCM2-MMI drive links menu with the > key and confirm with the >> key.
- Read out values from the display field.

- Distribution breakage
diagnosis Using this menu item, you can read out the current time zone of the PCM2.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select 'PCM' in the control modules selection and confirm with the >> key.
- Select 'PCM2-MMI' in the 911 Turbo (996) function selection and confirm with the >> key.
- Select drive links menu item and confirm with the >> key.
- Select "Distribution breakage diagnosis" in the PCM2-MMI drive links menu with the > key and confirm with the >> key.
- Read out values from the display field.

- Distribution breakage
line diagnosis Under this menu item, it is possible to check the electrical and optical MOST during troubleshooting.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select 'PCM2-MMI' in the 911 Turbo (996) function selection and confirm with the >> key.
- Select drive links menu item and confirm with the >> key.
- Select "Distribution breakage line diagnosis" in the PCM2-MMI drive links menu with the > key and confirm with the >> key.
- Read out values from the display field.

Control Module PCM2 (Head Unit).
The PCM2 control module (head unit) includes the following components:

Internal:
PCM2 gateway
PCM2 Man Machine Interface (MMI)
Internal amplifier (optional, depending on the equipment)
Tuner
Single CD
Navigation (optional/rack)
VOCS (voice control system) (optional/insertion)
Wake-up and diagnosis distribution line control
Controller Area Network (CAN) Comfort
MOST switch

External:
External amplifier (optional, Harman or BOSE)
CD changer (CDC) (optional)
Telephone/telematics (optional)

The PCM2 consists of at least two but a maximum of four MOST nodes, (Gateway, MMI and Navigation and VOCS (optional)), which communicate with each other electronically via the MOST. Data outside the PCM2 is transferred via the MOST.

Input Signals
The following queries can be run using this menu item:
- keys code
- Increment steps

NOTE: Deactivate the 'automatic traffic announcement' before performing the diagnosis on the PCM2. If this is not done, the diagnosis will abort.

Menu Item Function

- Keys code Using this menu item, you can
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- select '911 Turbo (996)' in the vehicle type menu and confirm with the >> key.
- Select 'PCM2' in the control modules menu and confirm with the >> key.
- Select 'PCM2-MMI' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select 'Drive links' in the 911 Turbo (996) PCM2-MMI menu and confirm with the >> key.
- Select "Key code" in the PCM2-MMI drive links menu with the > key and confirm with the >> key.
- If it works correctly, when the operating keys are pressed the respective key code is shown on the display.

- Increment steps Using this menu item you can check whether rotary knob for the volume and selection counter work.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select 'PCM' in the control modules menu and confirm with the >> key.
- Select 'PCM2-MMI' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select 'Drive links' in the 911 Turbo (996) PCM2-MMI menu and confirm with the >> key.
- Select "Increment steps" in the PCM2-MMI drive links menu with the > key and confirm with the >> key.
- To check, turn volume control or selection counter. If they work correctly, the respective change is displayed on the Porsche System Tester II No. 9588.

Single CD
The CD player is part of the PCM2. It is used to update the navigation system.

Voice Control System (VOCS)
The VOCS is designed as a module box which can be pushed into the PCM2 (optional). After inserting, an electronic connector is automatically opened and the module is integrated into the MOST ring.

Telephone/Telematics
The telephone/telematics is available as an optional feature and is linked to the PCM2 via the optical waveguide.

Tuner
The tuner is part of the PCM2 (on the mainboard)

Unlock Counter
Interruptions occur in the system if perfect communication is no longer possible. If the relevant threshold values are exceeded, an entry is recorded in the appropriate control module and the 'unlock counter' is incremented.

External Amplifier
The external amplifier (Harman or BOSE) is available as an optional feature and is linked to the PCM2 via the optical waveguide.

Internal Amplifier
The tuner is part of the PCM2 (on the mainboard)

Wake-Up Function
In an idle state, all control modules that are connected to the MOST are in sleep mode. When the PCM2 is switched on, a 'wake-up signal' is sent via the gateway. This signal is answered by the MOST control modules that are connected via the optical MOST.
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