' 07 GL 450 trailer wiring question
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2007 GL 450
' 07 GL 450 trailer wiring question
I purchased an 07 GL 450 with a factory installed hitch. Bought the 5 pin plug and thought that was all I needed to do. Noticed that the trailer lights didn't work so took a look in the rear fuse box. There are no fuses installed for trailier wiring (70, 71, 72). Is there a module I need to purchase or simply the fuses? Does a dealer have to do the install (if a module is needed) or can a trailer hitch place accomplish this?
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2004 RX330, 2008 Scion xB, 2001 Honda Insight Hybrid, 2010 Toyot Prius v ATP
If it is, indeed, a "factory installed" hitch and not one purchased afterwards, it should have any module needed to run the brake lights (which also, by the way, adjusts other settings in the GL automatically, such as turning off the rear parking distance sensors and setting up the traction control to assist with trailer sway). If it was NOT installed at the factory, you may need to purchase the trailer control module that is installed with the trailer hitch. If so, sorry, it's expensive.
My own advice is, don't tow until you know.
STP
My own advice is, don't tow until you know.
STP
Thread Starter
Newbie
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2007 GL 450
thx. I guess I cannot confirm that it was factory as I bought the vehicle used. It is not a drawtite, Uhaul, etc and fits flush with the vehicle. Anyway, if I need the module and it looks as if I do (there is no where for to fuses to plug into) does the dealer need to install and if so (gulp) how much does it run?
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From: NW corner of CONUS
2008 GL 320 CDI, 2004 VW V10 Touareg TDI
dinbri1:
Go to http://www.startekinfo.com/StarTek/s...by_chassis.jsp and sign up (no charge for US owners), then enter your VIN. You will find the list of all factory installed options there. If you see the factory hitch there you are OK. There were several 'recall' type events involving the Signal Acquisition Module (SAM) which is the computer involved with operating with a trailer. (This - the SAM - is the reason the dealer add on of the hitch is so expensive). After you make this determination, you SHOULD check with a dealer to determine if all the computer updates involving the SAM (with factory hitch) have been done. If they weren't they should be done under warranty.
Go to http://www.startekinfo.com/StarTek/s...by_chassis.jsp and sign up (no charge for US owners), then enter your VIN. You will find the list of all factory installed options there. If you see the factory hitch there you are OK. There were several 'recall' type events involving the Signal Acquisition Module (SAM) which is the computer involved with operating with a trailer. (This - the SAM - is the reason the dealer add on of the hitch is so expensive). After you make this determination, you SHOULD check with a dealer to determine if all the computer updates involving the SAM (with factory hitch) have been done. If they weren't they should be done under warranty.
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'10 CL550, '12 GL550
There's also a safety recall on the factory hitch--some additional wiring.
Your dealer will perform this recall for anyone at any mileage and at any age until it's done. Check with dealer to see if yours has been done. This will give you a quick idea whether your hitch was factory installed, as they will have records of that.
Your dealer will perform this recall for anyone at any mileage and at any age until it's done. Check with dealer to see if yours has been done. This will give you a quick idea whether your hitch was factory installed, as they will have records of that.
MBWorld Fanatic!
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From: Scottsdale, AZ
2004 RX330, 2008 Scion xB, 2001 Honda Insight Hybrid, 2010 Toyot Prius v ATP
MBWorld Fanatic!
Joined: May 2007
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From: Scottsdale, AZ
2004 RX330, 2008 Scion xB, 2001 Honda Insight Hybrid, 2010 Toyot Prius v ATP
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2008 GL 320 CDI, 2004 VW V10 Touareg TDI
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From: Albuquerque
'10 CL550, '12 GL550
Sorry if M-B changed policy since I signed up. I know my 'free' access was good until the end of August (one year since I signed up) but I haven't had occasion to try since so I don't know what happens now. Maybe lkchris (Kent) knows for sure. I DO know you have to give them a credit card number but it is NOT charged a fee.
The VIN check is in the parts system (called a datacard).
They ask for a credit card when subscribing to the free parts system only to verify you live in USA because this service is only available to USA residents. They don't charge the card.
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2014 Black SLK 55 AMG, Black 2015 GL 550, 2011 Blue GLK 350
I purchased an 07 GL 450 with a factory installed hitch. Bought the 5 pin plug and thought that was all I needed to do. Noticed that the trailer lights didn't work so took a look in the rear fuse box. There are no fuses installed for trailier wiring (70, 71, 72). Is there a module I need to purchase or simply the fuses? Does a dealer have to do the install (if a module is needed) or can a trailer hitch place accomplish this?
