Replacing Trailer Hitch Control Unit

NOTE: Voltage drop

Irreparable damage to control unit
Damage to control unit
Fault entries in the control unit
Control unit programming/coding is aborted
Malfunctions in the control unit, even during programming
→ Switch off ignition before disconnecting the control unit.

→ Make sure that the power supply is not interrupted during programming/coding.

→ Connect the battery charger with at least > current 90 A > to the vehicle battery.

Information

The terms "Ignition on" and "Starting engine" are re-defined for fully electric vehicles (battery electric vehicles - BEV).

Establishing operational readiness/Ignition on:

Prerequisites for establishing operational readiness: High-voltage battery is sufficiently charged, remove vehicle charging cable from the vehicle charge port, put driver's key in the emergency start tray.

Establishing operational readiness automatically: Get into the vehicle and close the driver's door. The driver's key is recognized inside the vehicle. Operational readiness is established.

Establishing operational readiness manually: Press Start/Stop switch. The driver's key is recognized inside the vehicle. Operational readiness is established.

Establishing operational readiness/Starting engine:

Establish operational readiness and engage transmission range. The vehicle is now ready to drive and can be moved.

Ending operational readiness/Switching off ignition

Ending operational readiness automatically: Get out of the vehicle with the driver's key and close the driver door. The driver's key is no longer detected outside the vehicle. Operational readiness ends.

Ending operational readiness manually: Press Start/Stop switch until the instrument cluster is switched off.

Ending driving readiness/Stopping engine

Vehicle is stationary: Press the P button on the instrument cluster. The vehicle is parked.

Information

The instructions in the Tester 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 additional information may appear in the Tester .

Connect the Tester to the vehicle and start it. Establish operational readiness on the vehicle.
Place original remote control (hand-held transmitter) in emergency start tray.

Courtesy of PORSCHE CARS NORTH AMERICA, INC.

Emergency start tray
Select the vehicle type if necessary.
Select the Trailer hitch control unit in the overview. Press F12 to continue. "Create vehicle analysis log (VAL)?" appears. Press F11 to continue.
Select Coding/programming .
Select Automatic coding . Press F12 to continue.
1. 6.1 The Tester displays the message: Coding was completed successfully.
Select Drive links/checks .
Trailer hitch must now be selected.
1. 8.1 Calibrate trailer hitch must be selected.
2. 8.2 Read and follow the instructions and information on the Tester.
3. 8.3 Calibrate trailer hitch according to menu support.
Go back to the overview .
In the overview , press F7 to switch to the Additional menu .
Read out all fault memories , work through faults that are stored if necessary and clear the fault memories.
Exit the diagnostic application. End operational readiness on the vehicle. Disconnect the Tester from the vehicle.