Introduction
Introduction
PSM 5.3 (Porsche Stability Management)
Diagnosis software number: PSM04XX
911 Carrera 4 (996) as of model year 1999 (x)
PSM 5.7 (Porsche Stability Management)
Diagnosis software number: PSM05XX
911 Carrera (996)/911 Carrera 4 (996) as from model year 2000 (Y)
NOTE: PSM was first instated as standard in the 911 Carrera 4 in 1999. This system is marked by PSM 5.3. System PSM 5.7 is installed in the 911 Carrera 4 and on request in the 911 Carrera 2 from 2000. The scope of functions is the same in both vehicles. The booster pump of the 911 Carrera 2 is not located at the hydraulic unit as in the 911 Carrera 4 but on the opposite side at the front end of the vehicle.
For a perfect functioning of the system, the following points must be observed:
- The battery must be securely connected.
- The brake fluid level must be at the correct level.
- The system must not leak.
- Tyre size, air pressure and the condition of the tyres must be satisfactory.
General Instructions/Safety Instructions
The following points must be observed during vehicle diagnosis:
- In the case of some faults in the PSM system, the Tiptronic transmission may switch to limp-home because it is lacking several important data.
- In the case of a defective control unit in the PSM 5.7, the entire hydraulic unit must be replaced.
- The control unit is separate from the hydraulic unit in the PSM 5.3 and can be replaced without the hydraulic unit in the case of a fault.
- In the case of a defective pressure sensor, the entire hydraulic unit must be replaced.
- When replacing the hydraulic unit, the control unit must be coded and the steering-angle sensor must be calibrated.
- The steering-angle sensor must be calibrated for all work on the running gear.
- After troubleshooting or repairs, erase the fault memory with the Porsche System Tester II No. 9588 and carry out a test drive.
- After the test drive, read out the fault memory with the Porsche System Tester II No. 9588 again.
CAUTION:
Danger of damage due to improper handling of batteries and control module plug connections.
- Disconnect the battery connection terminals only when the engine is switched off.
- Start the engine only when the battery connection terminals are properly connected.
- Pull off or push on plug connections for the control units or other electronic components only when the ignition is switched off.
- Disconnect the negative terminal of the battery before welding work on the vehicle.
Communication Between Control Module And Porsche System Tester II No. 9588
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
- Ignition on
- Battery positive voltage > 11 V
General Information On The Fault Memory
- The fault memory of the control unit can save up to three different faults simultaneously
- If all three fault memories are occupied, the new fault overwrites the oldest fault
- The contents of the fault memory are retained even when the unit is removed
- It is possible to reset faults in the control unit only after an "ignition reset (off - on)" procedure
Diagnostic Conditions
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
The possible fault causes that may be 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
The fault memory Info key F8 on the Porsche System Tester II No. 9588 can be used to access the extended fault memory. This information should be saved using the F4 key and printed out.
The following information can be displayed:
- Fault type
The following fault types are possible:
- -- (No details available)
- Short circuit to B+
- Short circuit to ground
- Signal implausible
- No signal change
- Open circuit/short circuit to B+
- Open circuit/short circuit to ground
- Open circuit
- Below limit value
- Above limit value
- Fault status
The following status types are possible:
- Present - at the time of the previous control-unit routine (Refer diagnostic conditions)
- Not present - at the time of the previous control-unit routine (Refer diagnostic conditions)