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External Harman Amplifier Control Module Function



External Harman Amplifier Control Module Function

Terminating Resistors On 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 can be coded on a vehicle and country-specific basis.

Menu item Function

- Vehicle type vehicle
coding The external Harman amplifier corresponding to the vehicle type can be coded 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 unit menu and confirm with the >> key.
- Select 'External Harman amplifier' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Coding' in the 911 (996) external Harman amplifier function selection and confirm with the >> key.
- Select "Vehicle type vehicle coding" in the 911 (996) external Harman amplifier function selection and confirm with the >> key.
- Select "911 (996)" in the menu and code with the F8 key.
- Vehicle version vehicle
coding The PCM2 GW corresponding to the vehicle version can be coded 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 unit menu and confirm with the >> key.
- Select 'External Harman amplifier' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Coding' in the external Harman amplifier function selection and confirm with the >> key.
- Select 'Vehicle type vehicle coding' in the external Harman amplifier coding function selection and confirm with the >> key.
- Select the relevant version 'Coupe, Cabrio, Targa' in the menu and code with the >> key.
- Right/left-hand drive
vehicle coding The external Harman amplifier corresponding to the vehicle configuration can be coded 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 'External Harman amplifier' in the PCM2 function selection and confirm with the >> key.
- Select 'Coding' in the external Harman amplifier function selection and confirm with the >> key.
- Select "Right/left-hand drive vehicle coding" in the external Harman amplifier coding function selection and confirm with the >> key.
- Select "Right or left-hand drive" in the menu corresponding to the vehicle equipment and code with the F8 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.

Function Of The Components







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 not possible.

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 using 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 'External Harman amplifier' in the 911 (996) PCM2 function selection and confirm with the >> key.
5. Select 'Identification' in the 911 (996) external Harman amplifier 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 following values under the 'Actual values' menu item:
- Vehicle speed
- Transmission errors
- Unlock counter
- Supply voltage

Menu item Function

- Vehicle speed You can read out the speed during troubleshooting under 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 'External Harman amplifier' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Actual values' in the 911 (996) external Harman amplifier function selection and confirm with the >> key.
- Select 'Speed' in the 911 (996) external Harman amplifier actual values function selection and confirm with the >> key.
- Read out values from the display field.
- Transmission errors It is possible to check the electrical and optical MOST during troubleshooting under 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 'External Harman amplifier' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Actual values' in the 911 (996) external Harman amplifier function selection and confirm with the >> key.
- Select 'Transmission errors' in the 911 (996) external Harman amplifier actual values function selection and confirm with the >> key.
- Read out values from the display field.
- Unlock counter It is possible to check the electrical and optical MOST during troubleshooting under 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 'External Harman amplifier' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Actual values' in the 911 (996) external Harman amplifier function selection and confirm with the >> key.
- Select the "Unlock counter" menu item using the > key and confirm your selection with the >> key.
- Read out values from the display field.
- Supply voltage You can check the supply voltage of the external Harman amplifier during troubleshooting 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 'External Harman amplifier' in the 911 (996) PCM2 function selection and confirm with the >> key.
- Select 'Actual values' in the 911 (996) external Harman amplifier function selection and confirm with the >> key.
- Select 'Supply voltage' in the 911 (996) external Harman amplifier actual values function selection 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; this results in a 'lock (connection)'. The lock is maintained until the signal disappears, i.e. an '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 - Optical/Electrical
MOST signals are transferred electrically within the PCM/CDR23 and optically outside of the PCM/CDR23. 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. Internally, the CDR23 consists of one node (GW), which is installed in the CDR23.

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 data is transferred outside of the CDR23 via the optical waveguide, which creates a connection to the nodes in the external MOST control modules such as external amplifiers and/or CD changers (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 modules are 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 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.

Navigation
The navigation module is designed as a module box, which can be inserted into 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

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 It is possible to check the electrical and optical MOST during troubleshooting under this menu item.
- Connect and start the Porsche System Jester 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 'External Harman amplifier' in the 911 (996) PCM2 function selection and confirm with the >> key
- Select 'Input signals' in the 911 (996) external Harman amplifier function selection and confirm with the >> key.
- Select "3dB lowering" in the external Harman amplifier input signals function selection using the > key and confirm with the >> key.
- Read out values from the display field.

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:
- Antenna diversity test
- Set tuner frequency
- Reset
- Wake-up sequence of the MOST system

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 with 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:
- MOST bus switch on
- MOST bus switch off
- MOST power reduction - start
- MOST power reduction - stop
- Output switch on
- Output switch off
- Volume - minimum value
- Volume - centre position
- Volume - maximum value
- Front fader
- Middle fader
- Rear fader
- Left balance
- Central balance
- Right balance
- Bass - minimum value
- Bass - centre position
- Bass - maximum value
- Treble - minimum value
- Treble - centre position
- Treble - maximum value
- MOST switch open
- MOST switch closed
- Mute off
- Mute on

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.

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 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, then communication will be established with all control units. The MOST switch will now be held open.
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