Operation CHARM: Car repair manuals for everyone.
Home >> Porsche >> 2004 >> 911 Turbo AWD (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 CDR23 >> CDR23 Control Module Function >> Terminal Resistance

Terminal Resistance



Control Unit Function (part 1)

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.

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 CDR23 gateway, via the optical MOST outside of the CDR23.

CD Changer (CDC)
The CDC is available as an optional feature and is linked to the CDR23 via the optical waveguide.

Coding
Under this menu item "change code", it is possible to code the CDR23.

Menu Item Function

- CDR23 code After replacing the CDR23, it is possible to enter the CDR23 code under this menu item.
- 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 'CDR23' in the CDR23 function selection menu and confirm with the >> key.
- Select 'coding' in the CDR23 function selection menu and confirm with the >> key.
- Select 'CDR23 code' in the CDR23 function selection menu and confirm with the >> key.
- Enter CDR23 code and code with the F8 key.

- Traffic information
volume boost Using this menu item, you can code the traffic information volume boost.
- 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 'CDR23' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select 'coding' in the CDR23 function selection menu and confirm with the >> key.
- Select 'increase traffic information volume' in the CDR23 coding menu and confirm with the >> key.
- Enter desired value for the radio information volume boost and code with F8 key.

- NDV (Noise-dependent
volume control) Using this menu item, you can code the traffic information volume boost according to noise level:
- 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 selection menu and confirm with the >> key.
- Select 'CDR23' in the CDR23 function selection menu and confirm with the >> key.
- Select 'coding' in the CDR23 function selection menu and confirm with the >> key.
- Select "NDV" in the CDR23 coding menu and confirm with the >> key.
- Enter the desired noise level-dependent volume boost and code with F8 key.

- Vehicle type
vehicle coding: Using this menu item, you can read out the vehicle type coding.
- 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 'CDR23' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select 'coding' in the CDR23 function selection menu and confirm with the >> key.
- Select 'vehicle type coding' in the CDR23 coding menu and confirm with the >> key.
- Select vehicle type '911 Turbo (996)' and code with F8 key.

- Vehicle type
vehicle version Using this menu item, you can code the vehicle version:
- 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 'CDR23' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select 'coding' in the CDR23 function selection menu and confirm with the >> key.
- Select "vehicle type coding" in the CDR23 coding menu and confirm with the >> key.
- Select respective vehicle type and code with F8 key.

- With/without air
conditioning Using this menu item, you can code the equipment with/without air conditioning:
- 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 'CDR23' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select 'coding' in the CDR23 function selection menu and confirm with the >> key.
- Select "with/without air conditioning" in the CDR23 coding and confirm with the >> key.
- Depending on equipment, select with/without and code with F8 key.

- Right/left-hand drive
vehicle coding Using this menu item, you can code the vehicle coding right/left-hand drive:
- 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 'CDR23' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select 'coding' in the CDR23 function selection menu and confirm with the >> key.
- Select "vehicle type coding right/left-hand drive" in the CDR23 coding and confirm with the >> key.
- Enter existing equipment and code with the F8 key.

- Production mode Under this menu item you can switch off the production mode (low-current mode) of the CDR23 when the vehicle is delivered. The current condition is not displayed.
- 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 'CDR23' in the 911 Turbo (996) function selection menu and confirm with the >> key.
- Select 'coding' in the CDR23 function selection menu and confirm with the >> key.
- Select "production mode on/off" in the CDR23 coding and confirm with the >> key.
- Select 'production mode on' with the > key and code with the F8 key.

- Tuner parameter Under this menu item you can code the tuner parameters (country-specific tuner adjustment) according to the country of admission.
- 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 selection menu and confirm with the >> key.
- Select 'CDR23' in the CDR23 function selection menu and confirm with the >> key.
- Select 'coding' in the CDR23 function selection menu and confirm with the >> key.
- Select "tuner parameter" in the CDR23 coding menu and confirm with the >> key.
- Select the 'country code' that corresponds to the country of admission with the > key 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 distribution line diagnosis 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.

Gateway
The gateway is integrated in the CDR23. It is a fixed component of each CDR23. It provides a connection from the CAN Comfort to the MOST 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)
- 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 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 'CDR23' in the 911 Turbo (996) CDR23 function selection menu and confirm with the >> key.
5. Select the "Identification" menu item and confirm with the >> key.
6. The message "Diagnosis software number; CDR23 parts number" appears on the display
7. Using the F8 key you can call up the 'Extended identification'. The following data is displayed:
- CRIN (Car Radio Identification Number)
- VIN (Vehicle Identification Number)
- Parts number
- System supplier ECU hardware no. (cw, year)
- System supplier ECU hardware version no.
- System supplier ECU software no. (cw, year)
- System supplier ECU software version no.
- Porsche workshop no.
- Diagnosis software number
- Date OCU manufacturing (YYY.MM.DD)

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

Menu Item Function

- 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 '911 Turbo (996)' in the vehicle type menu and confirm with the ->| key.
- Select 'PCM' in the control module selection menu and confirm with the >> key.
- Select 'CDR23' in the 911 Turbo (996) CDR23 function selection menu and confirm with the >> key.
- Select 'actual values' in the CDR23 function selection menu and confirm with the >> key.
- Select "unlock counter" in the CDR23 actual values menu and confirm with the >> key.
- Read out displayed values.

- Transmission fault Using this menu item, you can read out the transmission fault.
- 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 selection menu and confirm with the >> key.
- Select 'CDR23' in the 911 Turbo (996) CDR23 function selection menu and confirm with the >> key.
- Select 'actual values' in the CDR23 function selection menu and confirm with the >> key.
- Select "transmission fault" in the CDR23 actual values menu and confirm with the >> key.
- Read out displayed values.

- Traffic information
volume boost Using this menu item, you can read out the coded traffic information volume boost.
- 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 selection menu and confirm with the >> key.
- Select 'CDR23' in the 911 Turbo (996) CDR23 function selection menu and confirm with the >> key.
- Select 'actual values' in the CDR23 function selection menu and confirm with the >> key.
- Select "traffic information volume boost" in the CDR23 actual values menu and confirm with the >> key.
- Read out displayed values.

- Supply voltage Using this menu item, you can read out the supply voltage of the CDR23.
- 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 selection menu and confirm with the >> key.
- Select 'CDR23' in the 911 Turbo (996) CDR23 function selection menu and confirm with the >> key.
- Select 'actual values' in the CDR23 function selection menu and confirm with the >> key.
- Select "supply voltage" in the CDR23 actual values menu and confirm with the >> key.
- Read out displayed values.

Lock/Unlock
A lock occurs when the signal sent from the CDR23 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'.

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.

Menu Item Function

- MOST actual
installations list Under this menu item you can display the components which are recognized as functional by the system and which have been entered in the MOST actual installations list.
- 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 selection menu and confirm with the >> key.
- Select 'CDR23' in the 911 Turbo (996) CDR23 function selection menu and confirm with the >> key.
- Select 'MOST actual installations list' in the CDR23 function selection menu and confirm with the >> key.
- Only those components which are recognized by the system are listed (depending on equipment).

- MOST required
installations list Using this menu item, you can read out the transmission fault.
- 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 selection menu and confirm with the >> key.
- Select 'CDR23' in the 911 Turbo (996) CDR23 function selection menu and confirm with the >> key.
- Select 'MOST required installations list' in the CDR23 function selection menu and confirm with the >> key.
- Select "components from the selection list which correspond with the vehicle equipment" and code with the F8 key.

pro multis · About Operation CHARM