Trailer Hitch: Service Precautions

General Instructions/Safety Instructions

NOTE:
- The trailer hitch is available as a feature that can be detached manually or one that can be adjusted electrically. The latter has additional components and functions; these are included in this description and identified as additional equipment. The automatic pivoting action of the trailer hitch can be activated and deactivated in the 'Coding' menu item in the Porsche System Tester II No. 9588.
- The trailer hitch control module monitors the electric circuits to the trailer, i.e. problems in the vehicle and trailer are recorded as faults in the trailer hitch control module. Only vehicle-related faults are described in these instructions.
- All lighting faults are saved only by the last trailer. This means that if another trailer is detected (plug inserted and then removed), all lighting faults are first erased.
- Use a suitable test cable (tool) or a trailer (which is OK) to check whether the fault is present on the vehicle or whether it originates from the trailer.
- 'Trailer detection' is only successful if a trailer cable, which is 'charged' (load connected, resistance in electric circuit) is inserted.
- When troubleshooting, the status of the fault must be observed.
- The vehicle is equipped with a 5-pin plug for the North American market; this is used to connect a 'brake booster'.
- In the event of a short circuit to B+, ensure that positive voltage is connected only when the trailer connecting cable is inserted in the vehicle wiring harness.
- Once troubleshooting has been performed in the trailer hitch control module, the fault memory of the vehicle electrical system control module must be read out and erased.

WARNING:
Risk of injury and damage when retracting or extending the trailer coupling (trailer hitch).
- Make sure that no persons, animals or obstacles are in the movement range.
- Never retract the trailer hitch if, for example, bicycle racks or other parts are fitted.
Danger of injury and damage as a result of the vehicle's unusual handling behaviour caused by disconnected plugs or components.
- Never disconnect plugs while driving or drive with them disconnected.
- Drive only with fully installed and connected parts.

NOTE:
- Park Assist is deactivated for the rear area when the trailer connecting cable is inserted (detected trailer).
- Operation of the rear fog lights on the towing vehicle is disabled when the trailer connecting cable is inserted (detected trailer).
- The electric circuit in rear fog lights and reversing lights is not monitored for open circuits, i.e. 'open circuit' faults are not detected here. This feature was implemented because some trailers do not have these lights.
- When the trailer plug is pulled out of the socket for the first time, the alarm is triggered if the alarm system is armed. This means that the trailer is only protected against theft if it had been previously detected; vehicle was unlocked.

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.