Control Module: Service and Repair
WM 399519 Removing and installing control unit for four-wheel drive (PTM)
Tools
Technical values
Preliminary work
Preliminary work for control unit for four-wheel drive (PTM)
1. Move hood into service position. -> 6101IN Hood in service position
2. Remove carpet over the motor
2.1. To loosen the carpet, pull out the plastic clips using special tool 21 and take out the carpet. Disassembly tool, universal Nr.21
If a new four-wheel drive control unit is to be installed, read out the vehicle data from the four-wheel drive control unit and copy it to the new one.
3. PIWIS Tester 9718 must be connected to the vehicle before starting the System Tester. Switch on ignition. Press >> to continue.
4. Select vehicle type. Press >> to continue.
5. Carry out automatic search of control units.
6. Select PTM with the cursor keys and press the >> key.
7. Select Control unit replacement with the cursor keys and press the >> key.
8. Select Read out values (vehicle data) with the cursor keys and press >>.
9. The message Values were read out appears on the Tester screen.
10. After replacing the four-wheel drive control unit, the data that was read out is loaded when the Control unit replacement menu is selected. See section entitled Programming control unit for four-wheel drive.
Removing control unit for four-wheel drive (PTM)
NOTICE
Voltage peaks
- Risk of damage to load or to the control unit
-> Remove the ignition key and switch off load before disconnecting or removing load.
Information
The control unit for four-wheel drive (PTM) is fitted above the DME control unit.
Both control units are bolted to the frame for the roll-over protection system. For details of accessibility, see Preliminary work.
1. Screw off the two fastening nuts -3- and remove the four-wheel drive control unit from the holder.
Unscrewing fastening nuts and releasing connector, shown on the Coupe
2. Release connector for the four-wheel drive control unit -a- and pull it off.
Installing control unit for four-wheel drive (PTM)
1. Insert electric connector into the four-wheel drive control unit until it engages securely -a-.
Inserting connector and securing control unit, shown on the Coupe
2. Place the four-wheel drive control unit on the holder and secure with the two fastening nuts -3-. => Tightening torque: 10 Nm (7.5 ftlb.)
Subsequent work
Subsequent work for control unit for four-wheel drive (PTM)
1. If the control unit for four-wheel drive (PTM) was replaced, the control unit must be programmed using the PIWIS Tester 9718.
2. Re-fit the carpet over the motor.
3. Move hood out of service position. -> 6101IN Hood in service position
Programming control unit for four-wheel drive
Information
The PIWIS Tester 9718 instructions take precedence since the description may be different with later Tester releases.
The procedure described here has been structured in general terms; different text or additions may appear in the PIWIS Tester 9718.
1. Connect the Porsche System Tester to the vehicle and start the System Tester. Switch on the ignition and press >> to continue.
2. Select vehicle type. Press >> to continue.
3. Carry out automatic search of control units.
4. Select PTM with the cursor keys and press the >> key.
5. Select Control unit replacement with the cursor keys and press the >> key.
6. Select Read out values (vehicle data) with the cursor keys and press >>.
7. The message Values were read out appears on the Tester screen. Press >>
8. Switch off ignition and replace control unit.
9. Switch to the Special functions menu and perform the vehicle handover using the F8 key.
10. In the Special functions menu, select Erase all fault memories , then press >>.
11. Carry out automatic search of control units.
12. Go to the Control unit replacement menu and select Write values >>. The data that was read out is now loaded.
13. The System Tester displays the message Coding write-in complete >>.
14. Change to the Coding menu, compare the coding with the vehicle equipment and re-code if necessary.
14.1. Select the vehicle type , press >> and code with F8.
15. Exit the menu, carry out a test drive, and read out the fault memory.
Coding control unit for four-wheel drive (PTM)
This procedure must be used if the values or coding cannot be read out from the control unit.
NOTICE
Voltage drop
- Risk of irreparable damage to control unit
- Risk of damage to control unit
- Fault entries in the control unit
- Coding in the control unit is aborted
- Malfunctions in control unit, even during programming
-> Prior to disconnecting the control unit, switch off the ignition and remove the ignition key.
-> Ensure that the power supply is not interrupted during programming.
-> Connect a battery charger with a current rating of at least => Nominal value: 40 A to the vehicle battery.
NOTICE
Voltage drop
- Risk of irreparable damage to control unit
- Risk of damage to control unit
- Fault entries in the control unit
- Coding in the control unit is aborted
- Malfunctions in control unit, even during programming
-> Prior to disconnecting the control unit, switch off the ignition and remove the ignition key.
-> Ensure that the power supply is not interrupted during programming.
-> Connect a battery charger with a current rating of at least => Nominal value: 40 A to the vehicle battery.
Information
The PIWIS Tester 9718 instructions take precedence since the description may be different with later Tester releases.
The procedure described here has been structured in general terms; different text or additions may appear in the PIWIS Tester 9718.
Information
The procedure described must be applied when a control unit has to be replaced and the tester function Control unit replacement cannot be used.
1. PIWIS Tester 9718 must be connected to the vehicle before starting it. Switch on the ignition and press >> to continue.
2. Select the vehicle type.
3. Switch to the Special functions menu and perform the vehicle handover using the F8 key.
4. In the Special functions menu, erase All fault memories by pressing >>.
5. Carry out automatic search of control units.
6. Using the >> key, move from the vehicle type to the list of control units.
7. Select PTM with the cursor keys and press the >> key.
8. Select Control unit replacement with the cursor keys and press the >> key.
Information
If the test step Control unit replacement - Read values cannot be run, the test step Control unit replacement - Write values must still be performed after installing the new control unit! This writes the basic identification data into the control unit.
9. Select the menu Write values >>.
10. System Tester displays Coding write-in complete >>.
11. Change to the Codings menu and compare the coding with the vehicle equipment. Re-code if necessary.
11.1. Vehicle type must be selected before pressing F8 to begin coding.
12. Exit the menu, carry out a test drive, and read out the fault memory.