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So my truck has both a 4 pin and a 7 pin wiring harness. I've never towed a trailer with electric brakes, so I don't know if those work, but the lights don't work when using the 7 pin only the 4 pin.
7 pin trailer not putting power out
- Thread starter The motor guy
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Have you checked the condition of the ground on the connector from the truck end? Electric brakes will need a 7 pin connector and a brake controller. I know the 3rd gen Dodge's don't have one so you'll need to source an aftermarket one.
If you've never towed with this vehicle before, on some of my previous trucks with the tow pkg. I've had to install a relay or two under the hood and / or dash to energize that 7 way connector.
Also if you're going to install a brake controller the Tekonsha P3 is the best aftermarket one I've ever had. The Prodigy would be my second choice.
Also if you're going to install a brake controller the Tekonsha P3 is the best aftermarket one I've ever had. The Prodigy would be my second choice.
With all the camper places around TX someone should be able to track down your issue. They make plug in testers and I carry one to test the receptacle before plugging in a trailer. I would bet you need to add a relay to get the circuit hot.
My latest controller is an Insight by Hopkins. Can put the readout and actuator in separate places. My readout is on the dash with velcro and actuator is close to the center console shifter. Also on sale at Amazon right now too with coupon
My latest controller is an Insight by Hopkins. Can put the readout and actuator in separate places. My readout is on the dash with velcro and actuator is close to the center console shifter. Also on sale at Amazon right now too with coupon
I had a 2008 Jeep, probably the same Body Control Module (BCM) as your dodge. the 7-pin was powered through separate relays so the trailer load would not impact the vehicle's own lighting. Once installed, the relays had to be enabled with a BCM configuration, which required giving the dealer a few bucks.
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The lights did work when I used a 7-4 pin adaptor, but then after a hurricane and my boat trailer being in water for a couple days it quit after that. So evidently something shorted out. That was back in 2008. Since then I just used a 2 foot extension on my boat trailer and hooked it into the other regular 4 pin under the bumper and it's been fine.
IIRC the 4 pin just has a 10 amp fuse and there is another bigger fuse that's like 20 or 30 amps for the 7 pin. It's not your typical spade connector type fuse either, unless that's the relay you guys are talking about? That's what it looks like is a relay.
IIRC the 4 pin just has a 10 amp fuse and there is another bigger fuse that's like 20 or 30 amps for the 7 pin. It's not your typical spade connector type fuse either, unless that's the relay you guys are talking about? That's what it looks like is a relay.
Can you test things with a meter?
What are you pulling now that needs a 7 pin. Is it 7 round pin or seven spades?
Many boats with disc brakes need a 5 pin to power the blocking solenoid when you do into reverse.
What are you pulling now that needs a 7 pin. Is it 7 round pin or seven spades?
Many boats with disc brakes need a 5 pin to power the blocking solenoid when you do into reverse.
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Originally Posted By: Donald
Can you test things with a meter?
What are you pulling now that needs a 7 pin. Is it 7 round pin or seven spades?
Many boats with disc brakes need a 5 pin to power the blocking solenoid when you do into reverse.
I'm going to have a bigger landscape trailer built and I'm deciding whether or not to get brakes for it. It will have a round 7 pin plug. It's electric brakes not the surge type like on a boat trailer.
Can you test things with a meter?
What are you pulling now that needs a 7 pin. Is it 7 round pin or seven spades?
Many boats with disc brakes need a 5 pin to power the blocking solenoid when you do into reverse.
I'm going to have a bigger landscape trailer built and I'm deciding whether or not to get brakes for it. It will have a round 7 pin plug. It's electric brakes not the surge type like on a boat trailer.
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7 spades in a round plug.
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Originally Posted By: Srt20
fuse blown
IIRC the prodigy is simple plug and play on that truck. Its already wired.
What kind of fuse is it? I looked a while back and it was some big add 20 amp fuse. Is it one fuse for everything? Lights and trailer brakes?
fuse blown
IIRC the prodigy is simple plug and play on that truck. Its already wired.
What kind of fuse is it? I looked a while back and it was some big add 20 amp fuse. Is it one fuse for everything? Lights and trailer brakes?
This is a question that would easily be answered by reading the truck's owner's manual.
The fuses may be under the hood. In the old F-150s there was a separate small box under the hood just for trailer light fuses. They were regular fuses.
The truck is wired for a brake controller but you would have to buy and install it. If you get the Dodge harness for it it will plug in directly.
The fuses may be under the hood. In the old F-150s there was a separate small box under the hood just for trailer light fuses. They were regular fuses.
The truck is wired for a brake controller but you would have to buy and install it. If you get the Dodge harness for it it will plug in directly.
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Ok looked at the fuse box and it's number 19. A 30 amp fuse. Looked ok to me. It just said trailer tow whatever that means. There is also a 20 amp spade fuse in spot 15 that says trailer lights.
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So if you tow a trailer with brakes without a brake controller, what happens? Do the trailer brakes just not function?
Originally Posted By: motor_oil_madman
So if you tow a trailer with brakes without a brake controller, what happens? Do the trailer brakes just not function?
Yes. The controller sends voltage to the brake wire to engage the trailer brakes. With no electricity applied, the wheels roll free.
So if you tow a trailer with brakes without a brake controller, what happens? Do the trailer brakes just not function?
Yes. The controller sends voltage to the brake wire to engage the trailer brakes. With no electricity applied, the wheels roll free.
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Ok thanks
There are also surge brakes, non-electric.
Originally Posted By: copcarguy
Originally Posted By: motor_oil_madman
So if you tow a trailer with brakes without a brake controller, what happens? Do the trailer brakes just not function?
But PLEASE do not do this!
Not that it's a great idea, but with a 3/4 ton pickup you can get away without working brakes up to maybe 8000 lbs.
However some of the newer 1/2 ton pickups seem to have high towing capacity and in those situations I would want working brakes on any trailer.
Originally Posted By: motor_oil_madman
So if you tow a trailer with brakes without a brake controller, what happens? Do the trailer brakes just not function?
But PLEASE do not do this!
Not that it's a great idea, but with a 3/4 ton pickup you can get away without working brakes up to maybe 8000 lbs.
However some of the newer 1/2 ton pickups seem to have high towing capacity and in those situations I would want working brakes on any trailer.
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