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ugh's avatar
ugh
Explorer
Apr 26, 2015

7 pin trailer connector - no 12 volt for charging

I took a tester and tested the 7 pin trailer connecter. All pins worked except for number 4 12 volt charger. Is there something wrong or do I need to do something to turn it on to test it? Like put it in gear or what? The truck was running in parked when I tested it.

2001 F250 5.4 RWD


Tow Vehicles

15 Replies

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  • enblethen's avatar
    enblethen
    Nomad
    Apr 27, 2015
    Wrong fuse. Check for another one. One in question is for charge only, I think the one you found is for the brake controller or the ignition control to energize the relay.
  • ugh's avatar
    ugh
    Explorer
    Apr 27, 2015
    remdog*1 wrote:
    Most trucks with tow package require a 20-30 amp fuse to be plugged in under the hood for the 12v to work. Check owners manual for location of the fuse.


    I just checked. The fuse is in place and it is fine. It is not dedicated for number 4 pin. A/C clutch, power door locks and other things uses the same fuse.
  • RoyB's avatar
    RoyB
    Explorer II
    Apr 27, 2015
    My 2010 Ford F150 had a envelope in the glove box with a 12VDC FUSE and RELAY in it with no instructions. Turned out these were required to be installed in the main fuse panel on top of the radiator to provide TOW VOLTAGE when the ignition key was turned ON.
  • remdog_1's avatar
    remdog_1
    Explorer
    Apr 26, 2015
    Most trucks with tow package require a 20-30 amp fuse to be plugged in under the hood for the 12v to work. Check owners manual for location of the fuse.
  • The_Texan's avatar
    The_Texan
    Explorer
    Apr 26, 2015
    Check the fuse panel under the hood. That is where the 12v originates and usually the manufacturer either does not hook up the wire, but it is there in the bundle, or they do not place a fuse in the holder or both.

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