Towbar electrics
08-30-2013, 07:22 AM
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2004 Mercedes S203 180 Kompressor estate
Towbar electrics
Good day
I have a 2004 W203 180 Kompressor (actually the S203 station wagon). i bought a towbar complete with electrics and installed the towbar and fitted the electrics. it was second hand and came with the original piggy back box (Anhängeranschluss) which I connected to the CAN. BUT, the lights for a trailer will not work. It has the 13 pin socket but I bought a 7 way converter for the traditional trailer plugs. I can't get the trailer lights to work. I get a constant 12Volt on terminal 2, irrespective if I switch lights, indicators, brake on and no power through any of the other lines. The wire was cut but i splined it back together with professional Hellermann connectors. My question is, is the trailer connector box toasted, does the car need programming after the trailer electrical system was added as it had no prior towbar? will it be cheaper to just buy a 7 way bypass relay and do it that way?
Any advise please
Thanx
Adolf
Cape Town, South Africa
I have a 2004 W203 180 Kompressor (actually the S203 station wagon). i bought a towbar complete with electrics and installed the towbar and fitted the electrics. it was second hand and came with the original piggy back box (Anhängeranschluss) which I connected to the CAN. BUT, the lights for a trailer will not work. It has the 13 pin socket but I bought a 7 way converter for the traditional trailer plugs. I can't get the trailer lights to work. I get a constant 12Volt on terminal 2, irrespective if I switch lights, indicators, brake on and no power through any of the other lines. The wire was cut but i splined it back together with professional Hellermann connectors. My question is, is the trailer connector box toasted, does the car need programming after the trailer electrical system was added as it had no prior towbar? will it be cheaper to just buy a 7 way bypass relay and do it that way?
Any advise please
Thanx
Adolf
Cape Town, South Africa
08-30-2013, 12:22 PM
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2019 C300 Wagon; '75 Triumph TR6; previous: 2004 C230 6spd sold after 17 years of driving
Here in North America we usually use a either a flat 5 pin connector or a round 7 pin connector however you need a powered amplified converter in order to power the lights on the trailer or it will throw lights out codes as well having very dim lighting
It is a rare site to see a merecedes towing anything here unless it is an SUV
It is a rare site to see a merecedes towing anything here unless it is an SUV
08-30-2013, 04:45 PM
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Hello Adolf,
I have a tow bar which was installed by the dealer before delivery. I understood it had to be programed to the cars electronics to work.
My MB tows very stably,
Good luck.
I have a tow bar which was installed by the dealer before delivery. I understood it had to be programed to the cars electronics to work.
My MB tows very stably,
Good luck.
Last edited by Carsy; 08-31-2013 at 06:38 PM.
08-30-2013, 10:03 PM
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2005 C Wagon (No snickering please!)
The trailer module needs to be plugged into the rear SAM, it might need one or two relays added to the rear SAM. It will be necessary to tell the rear SAM the trailer package is installed. You might also need to program the AGW to let it know the trailer is there.
There is a 13 pin harness from the adapter to the hitch. If you want trouble free operation without nagging from the dash about lamps, convert the trailer to 13 pin wiring. The 7 way adapters don't play well with Benz.
There are other trailer solutions from third parties that connect to the vehicle lamps and operate the trailer lamps. They are US made but they do work with generator trailers I have in South Africa. They live in Irene and are usually towed by an M class.
There is a 13 pin harness from the adapter to the hitch. If you want trouble free operation without nagging from the dash about lamps, convert the trailer to 13 pin wiring. The 7 way adapters don't play well with Benz.
There are other trailer solutions from third parties that connect to the vehicle lamps and operate the trailer lamps. They are US made but they do work with generator trailers I have in South Africa. They live in Irene and are usually towed by an M class.
