7 pin trailer hook up to charge battery
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7 pin trailer hook up to charge battery
My pressure washer battery will no longer charge from the 13hp honda motor .. I am using the 4 pin connector for the trailer lights .. I was wonderering if I can rig something up to the 7 pin connector in order to charge the little 12volt battery while I am driving the truck .. if so what guage wire should I use
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From: Under the flightpath of old ORD 22R
Don't see why not, that is what it is made for ( changing a small 12V battery, albeit for the brakes normally ).
The factory trailer tow install directions call the trailer battery feed a max 11.5 A load, with a max wire length of 50' of 10 AWG wire.
If the battery is drawing a good charge from the truck, might be best to stick with 10 AWG ( current draw reasons ), and make sure you have the same size ground wire for the charging, don't rely on the 4 pin trailer tow adapter's 16 AWG wire for the ground.
The factory trailer tow install directions call the trailer battery feed a max 11.5 A load, with a max wire length of 50' of 10 AWG wire.
If the battery is drawing a good charge from the truck, might be best to stick with 10 AWG ( current draw reasons ), and make sure you have the same size ground wire for the charging, don't rely on the 4 pin trailer tow adapter's 16 AWG wire for the ground.
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Well I checked the big 7 pin plug and cant get the 12 volts of power .. I took my digi- multi meter and put the black to ground and then went around to where it says + on the plug and no juice.. so I checked each pin and no power until you turn the headlights on.. All the other connections work except for the 12V + .. I know I have 3 fuses under the hood I checked these and they are all good ( the 3 fuses control the left , right , and running lights ..
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From: Under the flightpath of old ORD 22R
Did you install the trailer tow battery charge relay ?
The trailer tow install kit, this is not installed ( neither is the trailer tow backup relay ) for the 99-03 MY trucks ( don't know why, it is in a plastic bag in the glove box from the dealer ).
The CJB ( aka Central Junction Box, cab fuse panel ) Fuse #23 is the power for the trailer tow battery charge relay coil ( and the flasher, 4x4 solenoids, etc ) so that should be OK.
The BJB ( aka Battery Junction Box, Engine Compartment fuse panel ) Fuse #5 is the power to the Trailer tow battery charge relay normally open contacts ( the power to the rear ) and the relay is #203 ( looks to be a 1/2 size ISO relay ).
If you do not have one you can use to test, you can jumper the normally open contacts in the relay socket, using a 1/8" male spade terminal ( think this still needs to be filed a bit for the width ), normal size is 1/4" wide.
Here is the pin out of the relay and the socket, make note of the pin orientation. I seem to be 70% sure the fog lamp relay is a half size ISO on the 99-03 MY trucks, if you want to use it to test with ( I know the 04-08 MY it is, that could be my confusion ).
Take a look to see if the relay is installed, and you can jumper ( as well as use a meter to test in the socket ) for the power at the rear.
The trailer tow install kit, this is not installed ( neither is the trailer tow backup relay ) for the 99-03 MY trucks ( don't know why, it is in a plastic bag in the glove box from the dealer ).
The CJB ( aka Central Junction Box, cab fuse panel ) Fuse #23 is the power for the trailer tow battery charge relay coil ( and the flasher, 4x4 solenoids, etc ) so that should be OK.
The BJB ( aka Battery Junction Box, Engine Compartment fuse panel ) Fuse #5 is the power to the Trailer tow battery charge relay normally open contacts ( the power to the rear ) and the relay is #203 ( looks to be a 1/2 size ISO relay ).
If you do not have one you can use to test, you can jumper the normally open contacts in the relay socket, using a 1/8" male spade terminal ( think this still needs to be filed a bit for the width ), normal size is 1/4" wide.
Here is the pin out of the relay and the socket, make note of the pin orientation. I seem to be 70% sure the fog lamp relay is a half size ISO on the 99-03 MY trucks, if you want to use it to test with ( I know the 04-08 MY it is, that could be my confusion ).
Take a look to see if the relay is installed, and you can jumper ( as well as use a meter to test in the socket ) for the power at the rear.
