Reversing made easy: 5 tips for maneuvering with the trailer

31. Juli 2018 um 16:12

Maneuvering with a trailer, parking and normal driving is often not as easy as one would wish. For driving with a trailer, you do not only have to get used to the big yoke, but also always pay attention to the restrictions of the driver’s license.

Even with practice, maneuvering and reversing with the trailer is often the most difficult t ask. To make sure that this is no longer a hurdle, we have put together five tips that make reversing with a trailer easier and prepare you for the next shunting.


What you should look out for when maneuvering

  1. Before you start driving and, for example, place the trailer in a parking space, you should make sure to adjust your mirrors so that you can see the trailer well. You may not neglect the interior mirror, this is of course much less used than usual, but it can be a help when reversing, since you can watch the trailer well in there and you can make out landmarks on the trailer. Of course, you might alreday know this from attaching, once you have no helper, attaching through landmarks on the trailer becomes easier even without help.
  2. When going backwards, make sure you drive slowly and steer. The smaller the trailer, the more it reacts to your steering movements. So, if you slow things down a bit, you can avoid the trailer suddenly taking a position that you either could not predict or could not easily undo. If you are slow, you can brake at any time and react to movements of the trailer.
  3. If you are not sure about the distances when parking, you should get a referrer to help you. If you do not have anyone, get out in between and see how much maneuvering space you still have.
  4. Make sure the angle does not get too steep when reversing. Because the steeper the angle is, the more elaborate is the parking in the parking space for you. If possible, drive a bit farther away from the parking space, then relax in a gentle arc.
  5. When choosing the parking space, you should make sure in advance that this is not only big enough, but you also have enough space to maneuver. Consider the length of your team and act accordingly anticipatory.

PDC shutdown: Why a car doesn’t recognise a trailer as an obstacle

30. Mai 2018 um 11:09

PDC shutdownFor some years now the PDC (Park Distance Control) system has been a standard feature of a car. When reversing sensors recognize obstacles behind the car, the board computer gives the driver an optical and/or acoustic signal.
In reality, a trailer should always be recognised as an obstacle, because it is directly at the tail end of the car. The PDC should really go haywire and permanently give warning signals. But it doesn’t – and why not? The reason is that the PDC shuts down, which is realised in various ways.
Heinz Hueber, Technical Manager of our Electrical Kit Department, explains how the Park Distance Control can be switched off with retro-fit trailer hitches and how the PDC shutdown functions.

1. Complete integration into the onboard electronics of the towing vehicle
If a towbar is installed by a car manufacturer in the factory, the electronics will be completely integrated with the onboard electronics of the towing car. Trailer operation is then activated in the board computer so that the board computer automatically knows when the trailer plug is inserted into the socket, e.g. that the car’s PDC and the rear fog light have to be switched off and possibly the trailer combination stabilisation switched on.
If a trailer hitch is retro-fitted the coupling electronics into the onboard electronics of the towing vehicle could also be integrated by a specialist workshop. For this, the control units in the vehicle must be manually activated with a tester (Caution! Not every tester can activate control units). There will be additional costs.
Unfortunately, not all car manufacturers authorise the access to the intelligent board electronics. Sometimes after a service at an authorized workshop the activation is reset. Therefore, the manufacturers of retro-fit trailer hitches solve the PDC shutdown by means of an electronic or mechanical trailer identification.

2. Control module in the electrical kit is used for recognition
A control module is built into the electrical kit delivered along with the towbar. This module detects the electrical load of the trailer lighting and passes on the information to the board electronics accordingly. Here we can latch into the board electronics of the towing vehicle, but without activation. The PDC shutdown is either switched on or off manually via a P-OFF switch, which many cars have, or automatically via an intelligent control module of the electrical kit, which also switches the trailer rear fog light on and off. Disadvantage: further driver assistance systems will not be adapted.

3. Micro-switch interrupts the power supply
The easiest solution is a mechanical micro-switch in the towbar socket. If the connector of the trailer is plugged in the micro-switch bumps off and interrupts the power supply to the PDC. At the same time the rear fog light will be switched off on the towing vehicle – only the rear fog light on the trailer will shine, not on the towing vehicle.

4. Digital communication via databus (CAN)
Nowadays many vehicles communicate via a databus. Here all information is digitally transported via a two-wire cable. The control modules are, connected with one another via the data bus, CAN (Controller Area Network) and communicate the necessary signals via the two cables, CAN-High and CAN-Low.
Technically the latest control modules of the trailer hitches could hook up into the CAN-Bus and communicate digitally with the onboard control units, but this is seldom the case.