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Function of the Components



PCM2 MMI Control Module Function (part 2)

Function Of The Components







Gateway
The gateway is integrated in the PCM2. Together with the MMI, it is a fixed component of each PCM2. It provides a connection to CAN comfort via its nodes. Diagnostic and useful data is exchanged with the 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/insertion)
- Man Machine Interface (MMI)
- Single CD
- Media Oriented Systems Transport (MOST), external bus (optical)

Identification
The diagnosis software number and the part numbers for the PCM2 can be read out under this menu item.
1. Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
2. Select '911 (996)' in the Vehicle type menu and confirm with the >> key.
3. Select 'PCM' in the Control units menu and confirm with the >> key.
4. Select 'PCM2 MMI' in the 911 (996) PCM2 function selection and confirm with the >> key.
5. Select "Identification" in the 911 (996) PCM2 MMI function selection and confirm with the >> key.
6. "Diagnosis software number; PCM2 part number." appears on the display.

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

Menu item Function

- Date You can read out the current date from the PCM2 using this menu item.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 (996)' in the Vehicle type menu and confirm with the >> key.
- Select 'PCM' in the Control units menu and confirm with the >> key.
- Select 'PCM2 MMI' in the 911 (996) function selection and confirm with the >> key.
- Select 'Actual values' in the 911 (996) PCM2 MMI function selection and confirm with the >> key.
- Select "Date" In the PCM2 MMI actual values function selection and confirm with the >> key.
- Read out values from the display field.
- Transmission errors You can read out the number of transmission errors from the PCM2 using this menu item.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 (996)' in the Vehicle type menu and confirm with the >> key.
- Select 'PCM' in the Control units menu and confirm with the >> key.
- Select 'PCM2 MMI' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Actual values' in the PCM2 MMI function selection and confirm with the >> key.
- Select 'Transmission errors' in the PCM2 MMI actual values function selection and confirm with the >> key.
- Read out values from the display field.
- Time You can read out the current time from the PCM2 using this menu item.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 (996)' in the Vehicle type menu and confirm with the >> key.
- Select 'PCM' in the Control units menu and confirm with the >> key.
- Select 'PCM2 MMI' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Actual values' in the PCM2 MMI function selection and confirm with the >> key.
- Select "Time" in the PCM2 MMI actual values function selection and confirm with the >> key.
- Read out values from the display field.
- MOST unlock counter You can read out the MOST unlock counter using this menu item.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 (996)' in the Vehicle type menu and confirm with the >> key.
- Select 'PCM' in the Control units menu and confirm with the >> key.
- Select 'PCM2 MMI' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Coding' in the PCM2 MMI function selection and confirm with the >> key.
- Select "MOST unlock counter" in the PCM2 MMI coding function selection and confirm with the >> key.
- Read out values from the display field.
- Traffic broadcast
loudspeaker boost You can use this menu item to read out the traffic broadcast loudspeaker boost setting.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 (996)' in the Vehicle type menu and confirm with the >> key.
- Select 'PCM' in the Control units menu and confirm with the >> key.
- Select 'PCM2 MMI' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Coding' in the PCM2 MMI function selection and confirm with the >> key.
- Select 'Loudspeaker boost' in the PCM2 MMI coding function selection and confirm with the >> key.
- Read out values from the display field.
- Time zone You can read out the current time zone from the PCM2 using this menu item.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 (996)' in the Vehicle type menu and confirm with the >> key.
- Select 'PCM' in the Control units menu and confirm with the >> key.
- Select 'PCM2 MMI' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Coding' in the PCM2 MMI function selection and confirm with the >> key.
- Select 'Time zone' in the PCM2 MMI coding function selection and confirm with the >> key.
- Read out values from the display field.

Lock/MOST 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; this results in a 'lock (connection)'. The lock is maintained until the signal disappears, i.e. a 'MOST unlock' occurs.

Man Machine Interface (MMI)
The MMI is part of the PCM2 (on the main board). It runs the gate-way commands via the wake-up signal line and the distribution line diagnosis. If control modules fail, this is reported to the gateway and saved there.

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. If the start signal is sent from the MMI to the MOST control units, the MOST switch will be opened and during reception of the corresponding light signal the connection will be maintained by the connected MOST control units. If the corresponding signal cannot be received or detected, the switch will re-close.

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.

MOST Actual And Required Installed Components Lists
All MOST control units connected to the PCM2 are entered in the 'MOST required installed components list'. The 'MOST actual installed components list' is compared with the 'MOST required installed components list' each time the PCM2 is started. If an 'installed MOST control module' is not reported, the MOST is switched off optically and a fault is recorded in the gateway.

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 and/or telephone/telematics (depending on the equipment). The gateway node represents the connection to CAN comfort.

Navigation
The navigation module is designed as a module box, which can be inserted in the PCM2 as an option. After the insertion, an electronic switch is opened automatically and the module is integrated into the MOST ring.

Input Signals
The following queries can be run using this menu item:
- Key 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

- Key code Under this menu item, it is possible to check that the operating buttons are functioning during troubleshooting.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 (996)' in the Vehicle type menu and confirm with the >> key.
- Select 'PCM' in the Control units menu and confirm with the >> key.
- Select 'PCM2 MMI' in the PCM2 function selection and confirm with the >> key.
- Select the Input signals menu item and confirm with the >> key.
- 'Key code' is displayed on the Porsche System Tester II No. 9588. The function is activated when you select it with > and confirm by pressing >>.
- If functioning correctly, the relevant code appears on the tester's display field when the operating buttons are activated.
- Increment steps This menu item shows the current status of the operating button.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 (996)' in the Vehicle type menu and confirm with the >> key.
- Select 'PCM' in the Control units menu and confirm with the >> key.
- Select 'PCM2 MMI' in the PCM2 function selection and confirm with the >> key.
- Select the Input signals menu item and confirm with the >> key.
- Select the Input signals menu item and confirm with the >> key.
- 'Increment steps' is displayed on the Porsche System Tester II No. 9588. The function is activated when you select it with >> and confirm by pressing >>.
- If functioning correctly, the relevant code appears on the tester's display field when the operating buttons are activated.

Input Signals
The following queries can be run using this menu item:
- Key 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

- Key code Under this menu item, it is possible to check that the operating buttons are functioning during troubleshooting.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 (996)' in the Vehicle type menu and confirm with the >> key.
- Select 'PCM' in the Control units menu and confirm with the >> key.
- Select 'PCM2 MMI' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Input signals' in the 911 (996) PCM2 MMI function selection and confirm with the >> key.
- 'key code' is displayed on the Porsche System Tester II No. 9588. The function is activated when you select it with > and confirm by pressing >>.
- If functioning correctly, the relevant code appears on the tester's display field when the operating buttons are activated.
- Increment steps This menu item shows the current status of the operating button.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 (996)' in the Vehicle type menu and confirm with the >> key.
- Select 'PCM' in the Control units menu and confirm with the >> key.
- Select 'PCM2 MMI' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Input signals' in the 911 (996) PCM2 MMI function selection and confirm with the >> key.
- 'Increment steps' is displayed on the Porsche System Tester II No. 9588. The function is activated when you select it with > and confirm by pressing >>.
- If functioning correctly, the relevant code appears on the tester's display field when the operating buttons are activated.

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

Special Function
The following functions can be run using this menu item:
- Read address book
- Write to address book
- Read user data
- Write user data
- Read coding
- Write coding
- MOST actual installed components list

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

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

The following drive links can be activated with the Porsche System Tester II No. 9588:
- Display colour black
- Display colour "coloured bars"
- Display colour blue
- Display colour red
- Display colour green
- Display colour white
- Set default values
- Ring break diagnosis
- Ring break line diagnosis

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

Menu item Function

- Display colour black The function Display colour black can be checked using this menu item.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 (996)' in the Vehicle type menu and confirm with the >> key.
- Select 'PCM' in the Control units menu and confirm with the >> key.
- Select 'PCM2 MMI' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Drive links' in the PCM2 MMI function selection and confirm with the >> key.
- Select 'Display colour black' in the PCM2 MMI drive link function selection and confirm with the F8 key.
- The display must show the correct colour.

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

- Set default values You can read out the set default values from the PCM2 MMI using this menu item.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 (996)' in the Vehicle type menu and confirm with the >> key.
- Select 'PCM' in the Control units menu and confirm with the >> key.
- Select 'PCM2 MMI' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Set default values' in the 911 (996) PCM2 MMI function selection and confirm with the >> key.
- Read out values from the display field.
- Ring break diagnosis A ring break diagnosis can be carried out using this menu item.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select '911 (996)' in the Vehicle type menu and confirm with the >> key.
- Select 'PCM' in the Control units menu and confirm with the >> key.
- Select 'PCM2 MMI' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Ring break diagnosis' in the 911 (996) PCM2 MMI function selection and confirm with the >> key.
- Read out values from the display field.
- Ring break 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 (996)' in the Vehicle type menu and confirm with the >> key.
- Select 'PCM' in the Control unit menu and confirm with the >> key.
- Select 'PCM2 MMI' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Ring break line diagnosis' in the 911 (996) PCM2 MMI function selection and confirm with the >> key.
- Read out values from the display field.

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

- Internal:
PCM2 gateway
PCM2 Man Machine Interface (MMI)
Amplifier (internal)
Tuner
Single CD
Navigation (optional/insertion)
VOCS (voice control system) (optional/insertion)
Wake-up and distribution line diagnosis 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 is transferred outside of the PCM2 via the optical MOST.

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

Tuner
The tuner is part of the PCM2 (on the main board).

MOST 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 internal amplifier is part of the PCM2 (installed on the main board).

Wake-up Function
All control units connected to the MOST are in sleep mode if the PCM2 is deactivated. When the PCM2 is switched on, a 'wake-up signal' is sent via the MMI. This signal is answered by the MOST control modules that are connected via the optical MOST. The check-back signals are stored as a MOST actual installed components list by the MMI and are compared with the MOST required installed components list. If a control unit is not detected, this will be reported to the gateway and stored. The MOST switch will then close and control units connected to the optical MOST will be switched off again. If the MOST actual installed components list matches the MOST required installed components list and the checkbacks occur within 40 ms, communication will be established with all control units. The MOST switch will now be held open.
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