7 pin to 5 pin problem -anybody have a fix?
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GL 350 Bluetec
7 pin to 5 pin problem -anybody have a fix?
2010 GL 350 Bluetec. Just bought new boat with heritage trailer. Trailer has electric brakes and 5pin plug. I bought the 7 to 5 pin adapter...it fits..but doesnt help the wiring...lights on trailer do not work. Anybody else have this problem and a fix?
Thanks,
Roy
Thanks,
Roy
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From: Scottsdale, AZ
2004 RX330, 2008 Scion xB, 2001 Honda Insight Hybrid, 2010 Toyot Prius v ATP
When I got my trailer hitch (MB hitch attached afterwards, way too expensive to do it that way compared to ordering it for those curious), they included the 7-4 conversion only, so I don't know if MB even makes one that's guaranteed "right." Of course, it's worth it to know if the plug is correctly wired to begin with. Having either a trailer with a 7 plug or a volt meter, a friend and some patience can help in that area!
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From: Dallas
09' Gl450
Hey Blue does the trailer have LED lights if so buy a connecter like this http://www.etrailer.com/p-V39008.html. This has a resistor built into the plug that is needed to "trick" the MB sensitive electronics. I have this plug and use to pull my boat trailer equipped with LED lights and have no problems. The plug can also be used for non LED trailers and it converts 7way to 5 or 4 pin.
Last edited by Madcmm; Jun 16, 2010 at 05:29 AM. Reason: Spelling
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From: New Orleans, LA, USA
04RX8GT+ / 09SLK55AMG / 2010Camaro2SSRS / 2010GL550
Great info! I had the same issue with my 2010 GL550... my GL operated the lights on my 2009 boat trailer, which has incandescent lights and 5 pins (one for brakes), with a standard $5 adapter. However, the LED lights on my 2010 double waverunner trailer with 4 pins would not work. This adapter from etrailer.com ( part # V39008 $15 USD) solved the issue and works with both of my trailers! Please be aware that leaving the adapter connected to my GL without also being connected to a trailer- caused a "brake light" warning in the dash.
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ml350
Looking at getting the Valley V39008 adapter (need to tow an LED trailer this weekend).
The product images online only show it being 5pin, which doesn't allow plugging in a 4pin cable connector.
How does it convert from 5pin to 4pin?
Does it come with two little rectangular insertable modules so you can pick either?
Thanks.
The product images online only show it being 5pin, which doesn't allow plugging in a 4pin cable connector.
How does it convert from 5pin to 4pin?
Does it come with two little rectangular insertable modules so you can pick either?
Thanks.
Junior Member
Joined: Jul 2009
Posts: 58
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From: Seattle, WA
2007 GL450
BlueRoy, do you have a brake controller wired into to your truck? If not, all you have is running lights, turn signal lights, and brake lights but not actual brakes on your trailer.
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From: B.C.
GL 320cdi, Chevrolet Avalanchero, GLE 350 (on order)
Junior Member
Joined: Jul 2009
Posts: 58
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From: Seattle, WA
2007 GL450
BlueRoy initally indicated the boat trailer has electric brakes and a 5-pin plug. 4-pin plugs are the minimum required for tail, stop, and turn lights. 5-pin plugs allow for another circuit typically for elctric brakes. 6-pin allows for an auxilary battery circuit (often to charge a break away switch battery or hydraulic pump battery for a dump trailer). 7-pin adds reverse lights or reverse lock-out for surge brakes. See link: http://www.etrailer.com/faq-wiring.aspx
Surge brakes are used on smaller boat trailers but you will often find electric systems on larger boat trailers. These systems are actually electric over hydraulic which use an actuator motor mounted up high which generates hydraulic pressure to the brake pistons. That way no electronic components get wet when launching the boat.
Therefore BlueRoy, if you have an electric brakers on your boat trailer you need to have a trailer brake controller installed to actuate them.
Surge brakes are used on smaller boat trailers but you will often find electric systems on larger boat trailers. These systems are actually electric over hydraulic which use an actuator motor mounted up high which generates hydraulic pressure to the brake pistons. That way no electronic components get wet when launching the boat.
Therefore BlueRoy, if you have an electric brakers on your boat trailer you need to have a trailer brake controller installed to actuate them.
Last edited by gbigpapa; Nov 30, 2011 at 07:29 PM.
Super Member
Joined: Mar 2008
Posts: 903
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From: B.C.
GL 320cdi, Chevrolet Avalanchero, GLE 350 (on order)
BlueRoy initally indicated the boat trailer has electric brakes and a 5-pin plug. 4-pin plugs are the minimum required for tail, stop, and turn lights. 5-pin plugs allow for another circuit typically for elctric brakes. 6-pin allows for an auxilary battery circuit (often to charge a break away switch battery or hydraulic pump battery for a dump trailer). 7-pin adds reverse lights or reverse lock-out for surge brakes. See link: http://www.etrailer.com/faq-wiring.aspx
Surge brakes are used on smaller boat trailers but you will often find electric systems on larger boat trailers. These systems are actually electric over hydraulic which use an actuator motor mounted up high which generates hydraulic pressure to the brake pistons. That way no electronic components get wet when launching the boat.
Therefore BlueRoy, if you have an electric brakers on your boat trailer you need to have a trailer brake controller installed to actuate them.
Surge brakes are used on smaller boat trailers but you will often find electric systems on larger boat trailers. These systems are actually electric over hydraulic which use an actuator motor mounted up high which generates hydraulic pressure to the brake pistons. That way no electronic components get wet when launching the boat.
Therefore BlueRoy, if you have an electric brakers on your boat trailer you need to have a trailer brake controller installed to actuate them.
Last edited by Brocktoon; Nov 30, 2011 at 10:38 PM.
Junior Member
Joined: Jul 2009
Posts: 58
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From: Seattle, WA
2007 GL450
If that's the case, it's a dangerous (perhaps illegal) trailer. I would not pull anything with electric brakes without a battery, and by extension a charging circuit. If you lose that trailer, it's a runaway. EVERY five pin trailer I have ever seen has been hydraulic or surge, never electric.
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From: Albuquerque
'10 CL550, '12 GL550
There are two versions of 5-pin converters ... since there appears to be two different wiring conventions.
the one still at my house that didn’t work with stepdaughter’s horse trailer is marked “center pin e. Brake.”
the one she’s using is marked marked something else. Probably from etrailer.com
the one still at my house that didn’t work with stepdaughter’s horse trailer is marked “center pin e. Brake.”
the one she’s using is marked marked something else. Probably from etrailer.com
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From: Allentown, PA
'08 GL 320 CDI
There are two versions of 5-pin converters ... since there appears to be two different wiring conventions.
the one still at my house that didn’t work with stepdaughter’s horse trailer is marked “center pin e. Brake.”
the one she’s using is marked marked something else. Probably from etrailer.com
the one still at my house that didn’t work with stepdaughter’s horse trailer is marked “center pin e. Brake.”
the one she’s using is marked marked something else. Probably from etrailer.com
