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Telephone/Telematics - Control Module Function



Telephone/Telematics Control Module Function

Terminating Resistors In The CAN
A terminating resistor is fitted to each end of the wiring to prevent reflection on the wiring. These terminating resistors are integrated into two control modules.

CAN Comfort
Communication between the Porsche System Tester II No. 9588 and the MOST control modules only takes place via the K lead to the instrument cluster. The data is transferred from the instrument cluster gateway to the MOST control modules, via CAN Comfort to the PCM2 gateway, via the electrical MOST in the PCM2 and via the optical MOST outside of the PCM2.

CD Changer (CDC)
The CDC is available as an optional feature and is linked to the PCM2 via the optical waveguide.

Coding Table










Coding
Under the menu item 'Modify coding', the PCM2 codes can be coded on a vehicle and country-specific basis.

Menu item Function

- External handset You can code an external telephone handset 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 'Telephone/telematics' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Coding' in the 911 (996) telephone/telematics function selection and confirm with the >> key.
- Select "Country coding" in the 911 (996) telephone/telematics coding function selection and confirm with the >> key.
- Select "External handset" from the menu item displayed and code it with the >> key.

Data Transfer Fault
If faults are detected when the data is decoded, this is known as a data transfer fault. The faults can arise when the data is encoded, when the data is transferred through an input level that is optically too low or when the data is decoded. A fault entry is not recorded.

Diagnosis Distribution Line
The diagnosis distribution line is an electrical lead, which, as a stub cable, connects the individual MOST control modules in the system with one another, The existing MOST control modules are checked at regular intervals during communication with the control modules via the electrical/optical MOST.

Installation Position Of The Control Module
The telephone control module is installed under the passenger's seat.

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 'Telephone/telematics' in the 911 (996) PCM2 function selection and confirm with the >> key.
5. Select 'Identification' in the 911 (996) telephone/telematics function selection and confirm with the >> key.
6. "Diagnosis software number; PCM2 part number." appears on the display.

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

Actual Values
The following can be read out under the 'Actual values' menu item:
- Transmission errors
- MOST unlock counter
- Signal strength
- Supply voltage

Menu item Function

- Transmission errors You can read out all transmission errors 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 'Telephone/telematics' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Actual values' in the 911 (996) telephone/telematics function selection and confirm with the >> key.
- Select 'Transmission errors' in the 911 (996) telephone/telematics 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 counters 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 'Telephone/telematics' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Actual values' in the 911 (996) telephone/telematics function selection and confirm with the >> key.
- Select 'MOST unlock counter' in the 911 (996) telephone/telematics actual values function selection and confirm with the >> key.
- Read out values from the display field.
- Signal strength You can read out the signal strength 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 'Telephone/telematics' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Actual values' in the 911 (996) telephone/telematics function selection and confirm with the >> key.
- Select 'Signal strength' in the 911 (996) telephone/telematics actual values function selection and confirm with the >> key.
- Read out values from the display field.
- Supply voltage You can read out the supply voltage 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 'Telephone/telematics' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Actual values' in the 911 (996) telephone/telematics function selection and confirm with the >> key.
- Select 'Supply voltage' in the 911 (996) telephone/telematics actual values 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 gateway 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 Actual And Required Installed Components Lists
All MOST control modules that are connected to the PCM2 are entered in the 'required installed components list'. The 'actual installed components list' is compared with the '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 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.

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:
- 3dB lowering
- Signal strength

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

- 3dB lowering 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 units menu and confirm with the >> key.
- Select 'Telephone/telematics' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Input signals' in the 911 (996) telephone/telematics function selection and confirm with the >> key.
- Select the menu item "3dB lowering" and confirm with the >> key.
- Read out values from the display field.
- Signal strength You can read out the MOST installed components list 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 'Telephone/telematics' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Input signals' in the 911 (996) telephone/telematics function selection and confirm with the >> key.
- Select the menu item "Signal strength" and confirm with the >> key.
- Read out values from the display field.

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:
- 3dB lowering

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

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 control and control for diagnosis of open circuit in distribution line
Controller Area Network (CAN) Comfort
MOST switch

- External:
External amplifier (optional, Harman or BOSE)
Telephone/telematics (optional)
CD changer (CDC), (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 via the electronic 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.

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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