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Home >> Porsche >> 2004 >> 911 GT2 (996) F6-3.6L Turbo >> Repair and Diagnosis >> Relays and Modules >> Relays and Modules - Accessories and Optional Equipment >> General Module >> Testing and Inspection >> Component Tests and General Diagnostics >> PCM2/CDR23 External Harman Amplifier >> External Harman Amplifier Control Module Function

External Harman Amplifier Control Module Function



Control Unit Function

Terminal Resistance On The CAN
To prevent reflection on the wiring the ends of the wires are each provided with a terminal resistor, which are integrated into two control modules.

Audio Tests
Manual and automatic audio tests are available for checking the loudspeaker system.

Individual manual selection
- front left, test frequency 1 kHz
- front right, test frequency 1 kHz
- rear left, test frequency 1 kHz
- rear right, test frequency 1 kHz
- left door box, test frequency 1 kHz
- right door box, test frequency 1 kHz

Menu Item Function

- Individual manual
selection Using this menu item, you can
- Connect and start the Porsche System Tester II No. 9588, start and switch on the ignition.
- Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select 'PCM' in the Control module menu and confirm with the >> key.
- Select 'Harman external amplifier' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select "Audio tests" in the menu and confirm with the >> key.
- Select 'Individual manual selection' in the Audio tests menu and confirm with the >> key.
- Select "911 Turbo (996)" and code with the F8 key.

Use the F8 key to start; the F5 key to increase the volume and the F6 key to lower the volume.

Automatic test
The existing loudspeakers can be controlled automatically using the Porsche System Tester II No. 9588.

Menu Item Function

- Automatic test Using this menu item, you can
- Connect and start the Porsche System Tester II No. 9588, start and switch on the ignition.
- Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select PCM' in the Control module menu and confirm with the >> key.
- Select 'Harman external amplifier' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select "Audio tests" in the menu and confirm with the >> key.
- Select 'Automatic test' in the Audio tests menu and confirm with the >> key.
- Select "911 Turbo (996)" and code with the F8 key.

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
It is possible to code the Harman amplifier according to the vehicle under this menu item.

Menu Item Function

- Vehicle type
vehicle coding It is possible to code the Harman external amplifier according to the vehicle type under this menu item.
- Connect and start the Porsche System Tester II No. 9588, start and switch on the ignition.
- Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select 'PCM' in the Control module menu and confirm with the >> key.
- Select 'Harman external amplifier' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select "Vehicle coding" in the menu and confirm with the >> key.
- Select 'Vehicle type coding' in the coding menu and confirm with the >> key.
- Select "911 Turbo (996)" and code with the F8 key.

- Vehicle type
vehicle version It is possible to code the Harman external amplifier according to the vehicle version under this menu item.
- Connect and start the Porsche System Tester II No. 9588, start and switch on the ignition.
- Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select 'PCM' in the Control module menu and confirm with the >> key.
- Select 'Harman external amplifier' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select "Vehicle version" in the menu and confirm with the >> key.
- Select 'Vehicle type coding' in the coding menu and confirm with the >> key.
- Select "911 Turbo (996)" and code with the F8 key.

- Right/Left-hand
drive vehicle coding It is possible to code the Harman external amplifier according to the vehicle model under this menu item.
- Connect and start the Porsche System Tester II No. 9588, start and switch on the ignition.
- Select '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select 'PCM' in the Control module menu and confirm with the >> key.
- Select 'Harman external amplifier' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select "Vehicle coding" in the menu and confirm with the >> key.
- Select 'Vehicle type coding right/left-hand drive' in the coding menu and confirm with the >> key.
- Select "Right/left-hand drive" from the menu, depending on the vehicle equipment, and code with the F8 key.

Data Transfer Fault
If faults are detected when the data is decoded, this is referred to as a data transfer fault. The faults can arise when the data is coded, 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 made.

Distribution Line Diagnosis
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 electrically/optically checked at regular intervals during communication with the control modules via the 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 then not possible.

Gateway
The gateway is integrated in the PCM2/CDR23. Together with the MMI, it is a fixed component of each PCM2 (not used for CDR23). 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 the Porsche System Tester II No. 9588 and switch on the ignition.
2. Select vehicle type 911 (996) and control module PCM2 and press the >> key.
3. Select the "Identification" menu item and press the >> key.
4. The message "Diagnosis software number; PCM2. parts number" appears on the display.

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

Menu Item Function

- Supply voltage Using this menu item, you can determine the supply voltage.
- 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 module menu and confirm with the >> key.
- Select 'Harman external amplifier' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select 'Actual values' in the 911 Turbo (996) menu and confirm with the >> key.
- Select 'Supply voltage' > in the menu and click on the > key. Confirm using the >> key.
- Read out values from the display field.

- Vehicle speed 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 'PCM' in the control module menu and confirm with the >> key.
- Select 'Harman external amplifier' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select 'Actual values' in the Harman external amplifier function selection menu and confirm with the >> key.
- Select 'Speed' > in the menu and click on the > key. Confirm using the >> key.
- Read out values from the display field.

- Unlock counter 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 vehicle type 911 (996) and control module PCM2 and confirm with the >> key.
- Select 'Actual values' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select "Unlock counter" in the Harman amplifier actual values menu item using the > key and confirm with the >> key.
- Read out values from the display field.

- Transmission fault 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' in the Control modules menu and confirm with the >> key.
- Select 'Harman external amplifier' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select the Actual values menu item and confirm with the >> key.
- Select 'Unlock counter' in the menu using 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.

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.

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 PCM2CDR23 and optically outside of the PCM2/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 ARS 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, CD changers 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 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.

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

- 3 dB lowering Under this menu item, it is possible to check the optical MOST during troubleshooting.
- Connect and start the Porsche System Tester II No. 9588 and switch on the ignition.
- Select vehicle type 911 (996) and control module PCM2-GW and press the >> key.
- Select the Input signals menu item and press the >> key.
- Select the "3 dB lowering" menu item using the > key and press 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.

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:
- 3 dB lowering
- Switching on the front left channel FL
- Switching off the front left channel FL
- Switching on the front right channel FR
- Switching off the front right channel FR
- Switching on the rear left and right channels RL + RR
- Switching off the rear left and right channels RL + RR
- Switching on the left subwoofer channel L
- Switching off the left subwoofer channel L
- Switching on the right subwoofer channel R
- Switching off the right subwoofer channel R
- Volume - minimum value
- Volume - centre position
- Volume - maximum value
- Mute off
- Mute on

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

Control Unit PCM2 (Head Unit)
The PCM2 control unit (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 breakage line control
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 outside the PCM2 is transferred via the optical MOST.

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 internal amplifier 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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