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I have a 08 GM 3500 and the ITBC all of a sudden is very…

Customer Question
I have a 08...

I have a 08 GM 3500 and the ITBC all of a sudden is very weak

Mechanic's Assistant: Are you fixing your 3500 yourself? What have you tried so far?

I checked both the 7 way plugs in the bed and factory on on bumber and all wiring is good. when manual slide is pressed it will barely activate the trailer brakes

Mechanic's Assistant: Have you checked all the fuses? Do you have a wiring diagram?

I have checked all the fuses regarding trailer all good

Mechanic's Assistant: Anything else you want the mechanic to know before I connect you?

I have even replaced the module by the frame in the back

Submitted: 7 months ago.Category: GMC
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Answered in 5 hours by:
12/8/2017
GMC Mechanic: Chris (aka-Moose), GMC Technician replied 7 months ago
Chris (aka-Moose)
Chris (aka-Moose), GMC Technician
Category: GMC
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When monitoring the voltage on the electric brake wire at the trailer plug. What is the voltage at max gain, brake pressed or slider moved?

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GMC Mechanic: Chris (aka-Moose), GMC Technician replied 7 months ago

Hello, Chris here again,

I am checking in to make sure you got everything you expected from my answer. The option to rate my response or reply is still available. I want to make sure you were pleased with what you paid for.

Thanks Chris

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Customer reply replied 7 months ago
Checking voltage tonight
GMC Mechanic: Chris (aka-Moose), GMC Technician replied 7 months ago

Okay

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Customer reply replied 7 months ago
Had 10 plus bolts at the 7 way pin. But still soft trailer brakes. Also adjusted all for brake pads on trailer so they are tight. Any idea?
GMC Mechanic: Chris (aka-Moose), GMC Technician replied 7 months ago

That is adequate voltage to get great brake application. You may want to see if your trailer ground is bad or the ground wire from the trailer 7pin to the truck 7 pin is making a poor connection. Next, I would check the trailer brakes to see if they too get 10+ volts? If so then check your grounds and see if your brake magnets are worn out.

Now that I have posted a partial or complete answer, you will see you can rate me. The deposit you have already paid is not transferred to me until you rate me. I would like to receive nothing less than 5-star excellent ratings. So if we are not there yet, please reply and let me help more. If you're not pleased, let me know because rating bad does not result in a refund, there are better options. Rating now will not close this post nor prevent replying. Thanks Chris

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Customer reply replied 6 months ago
There are less than 2 year old all four brakes installed. They can't be worn out that soon and with so few miles on them. I will check voltage on brakes and ground.
GMC Mechanic: Chris (aka-Moose), GMC Technician replied 6 months ago

I understand the frustration, but with the truck putting out adequate voltage I can not find a way to blame the truck.

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Customer reply replied 6 months ago
Zero frustration over here. Jist giving you background information about the components installed so we can accurately work the problem. I will try and trace a bad ground.
GMC Mechanic: Chris (aka-Moose), GMC Technician replied 6 months ago

Another thing you may want to try is using jumper cables and short pieces of wire from a battery to remotely power the trailer brake connector to see if you get the same results or more brake magnet force.

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