Some notes on the electric systems of Humbaur trailers

All of our trailers have safety lighting and a connector for the electric systems as standard fittings.

The colours of the wires for contact 9, 10, 11 and 13 can vary. Contact 10 in the connector must not be clamped on contact 9. It can damage the towing vehicle or the steering electronics of the towing vehicle. Please refer to the operating manual of the towing vehicle (trailer operation).

Notes on the pin assignment
Only use contacts 10 & 11 for the charging current – in accordance with DIN/ISO 11446. If these are not already installed/connected in the connector of the towing vehicle, the appropriate connections must be fitted. This charging lead should be connected to the battery via an isolating relay as soon as the ignition is switched on and the engine is running. Do not connect contact 11 with contact 13. The two earthing wires must be insulated on the trailer side. Please refer to the operating manual of the towing vehicle (trailer operation).

In the event of electrical problems, refer to your specialist workshop
Humbaur GmbH is not liable for any warranty claims or costs in respect of the trailer or towing vehicle arising from the incorrect allocation or alternative connection of the contacts. Please refer to the operating manual of the towing vehicle (trailer operation).

Trailer with battery
If the charging lead is correctly connected in accordance with DIN ISO 11446, then the trailer will be charged via the 13-pin socket when being towed. Please note this is primarily a trickle charge, not a full charging of the trailer battery. If you only go on short trips, the charging time may not be even sufficient for a trickle charge. The cross-sections of the cables in most towing vehicles are too small and the performance of the alternator is usually insufficient to charge an additional battery in the trailer fully. Moreover, some vehicle manufacturers do not permit charging via the charging lead. A discharged or weak supply battery can lead to defective motor-starting relays.
You should therefore check the output of the supply battery regularly. Fully charge the supply battery via an external battery charger. If you are not using the trailer for some time, maintain the battery performance with a trickle charge.

1Indicator leftLYellow
2Rear fog light54gBlue
4Indicator rightRGreen
5Light right58RBrown
6Brake lights54Red
7Light left58LBlack
No. Description Identification Colour Cross section
1 Indicator left L Yellow 1,5 mm
2 Rear fog light 54g Blue 1,5 mm
3 Earth for Contacts 1-8 31 White 2,5 mm
4 Indicator right R Green 1,5 mm
5 Light right 58R Brown 1,5 mm
6 Brake lights 54 Red 1,5 mm
7 Light left 58L schwarz 1,5 mm
8 Reversing light 1 grau / pink 1,5 mm
9 Continuous current/continuous plus (Empty) 4 Brown/Blue/Orange 2,5 mm
10 Charging cable 6 Brown/red 2,5 mm
11 Earth for Circuit No. 10 3 White/Black/Blue 2,5 mm
12 Trailer registration (empty) Contact No. 12 in the plug is connected to Contact No. 3 to indicate to the towing vehicle whether the trailer is connected.    
13 Earth for circuit Contact No. 9 (empty) White/red 2,5 mm  

Pin assignment plan for the 7-pin plug

Pin assignment plan for the 13-pin plug