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Body Control Module: Application and ID

Vehicle electrical system (BNSG)

Introduction - vehicle electric system control unit

Diagnosis software number: BSG 0101
Cayenne as of model year 2002

General instructions/safety instructions

CAUTION:
Danger of damage due to improper handling of batteries and control module plug connections.
- Never disconnect battery with engine running.
- Never start engine if battery terminal clamps are not connected securely.
- Never pull off or push on plug connections for the control modules or other electronic components when the ignition is switched on.
- Always disconnect the negative terminal of the battery and pull off all plug connections to the 'vehicle electrical system control module' when carrying out welding work on the vehicle.


WARNING:
Danger of injury and damage due to unusual vehicle handling when plugs or components are disconnected.
- Never disconnect plugs when the vehicle is in motion or drive the vehicle with plugs disconnected.
- Drive only with all parts fully installed and connected.


Communication between vehicle electrical system control module and Porsche System Tester II No. 9588

NOTE:
The following conditions must be met in order to establish communication between the vehicle electrical system control module and the Porsche System Tester II No. 9588:
- Porsche System Tester II No. 9588 connected to data link connector
- The battery voltage must be greater than 6.7 V

General information on the fault memory
The fault memory of the control module can save up to (X) different faults simultaneously. If all (X) fault memories are occupied, the new fault overwrites the oldest fault. The fault memory content of the 'vehicle electrical system control module' is maintained even in removed state.

Fault code setting conditions
Fault codes can be set in several circumstances, e.g.:
- battery disconnected
- plug connections disconnected
- faulty coding
- power failure
- etc.

In these circumstances, no fault is present in the system and the fault memory must be erased.

Troubleshooting procedure
Troubleshooting can only be performed when the fault is present. In other words, specific troubleshooting can only be performed in accordance with instructions (given under Diagnosis/troubleshooting for each fault code) if the entry has the status 'present' in the fault memory.

If the fault is currently 'not present', please check the following:
- Diagnostic conditions are met
- All plug connections and ground points of the affected current path are OK.
- View the fault frequency counter in the Porsche System Tester II No. 9588 using the fault memory Info key [F8] under 'Extended fault memory' and try to reach conclusions about eliminating any loose contacts in the system.

Diagnostic conditions

NOTE:
Important: Always connect a suitable battery charging device to the vehicle electrical system battery before starting diagnosis. All unnecessary loads must also be switched off.

NOTE:
The fault can only be identified if the requirements listed under 'Diagnostic conditions' are met. For this reason, the specified procedure must be observed after a fault is repaired:
1. Erase fault memory.
2. Satisfy the requirements listed under 'Diagnostic conditions'.
3. Read out fault memory again

Possible causes of fault

NOTE: The 'possible causes of fault' that are responsible for the fault are listed here. Please note that in certain circumstances further faults can be stored in the fault memory after troubleshooting (e.g. if plugs are disconnected). After carrying out repairs, read out the fault memory of all control modules and erase any faults.

Diagnosis/troubleshooting

NOTE: The fault memory Info key [F8] on Porsche System Tester II No. 9588 can be used to access the 'extended fault memory'. The following information can be displayed:

Fault type
The following fault types are possible:
- no display
- upper limit value exceeded
- lower limit value not reached
- mechanical fault
- no signal/communication
- no or incorrect basic setting/adaptation
- Short circuit to B+
- Short circuit to ground
- implausible signal
- open circuit/short circuit to ground
- open circuit/short circuit to B+
- Open circuit
- electrical fault in electric circuit
- please read out fault memory
- faulty
- cannot be checked now

Fault status
The following status types are possible:
- present
- not present

This information should be saved using the Save key [F4] and printed out.

NOTE:
Visual inspection: During troubleshooting, please check first that the affected pins on the control module plug connection are neither damaged nor corroded. The wires and plugs of the affected components must also be checked for external damage and correct contacts. Repair damaged or corroded pins if possible, otherwise replace affected pins. Repair or replace damaged wires.

NOTE:
Battery voltage: A battery voltage of between 11.4 and 14.5 V is required for troubleshooting. This must be checked and provided if necessary. Voltages as well as components or fuses (input side) must be guaranteed on the vehicle electrical system.