7 pin trailer connector - no 12 volt for charging

[ugh]

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

[ugh]

Bought the fuses and installed it. It is working now. Strange that it takes 2 relays and 2 fuses to get it to work. But, I like the idea that it only supply 12 volt when the key is turned on and not all the time.

Thank you for your help.

[ianmac23]

My GMC the dealer told me it was a dealer installed option. I did not like that answer because the dealer that I purchased it from did not give me the option. My local dealer installed it for free.

[lbrjet]

GM's are hot all the time, Ford's are hot only with the key on.

[Calicajun]

After reading OP post, I went out and check my 7 pin connector. Luckily mine is working just fine. 🙂

[LarryJM]

Blue Hill wrote:
I had the same issue. I connected the wire and installed the fuse, but now the terminal is hot all the time, regardless of whether or not the key is on.

Be careful the trailer ckts might be different (i.e. fuze, fuze and relay, etc.) and how they operate (i.e. KO or KOFF) depending on vehicle make and even year. AFAIK Ford uses a relay and separate fuzes that operate independently of the other main electrical ckts and are not operable for KOFF status.

Larry

[Blue_Hill]

I had the same issue. I connected the wire and installed the fuse, but now the terminal is hot all the time, regardless of whether or not the key is on.

[MitchF150]

oops.. Missed that you had the truck running.. Never mind.. 🙂

Mitch

[remdog_1]

That's it, just install fuse and check with tester. When you test it the key has to be on.:)

[ugh]

enblethen wrote:
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.

You are correct. I need to buy two more fuses.

[ugh]

RoyB wrote:
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.

That's it. The two relay was not installed. I found them in the glove compartment (hard to believe it was in there after 15 years) I just installed it, but it requires two additional fuses. I need to go buy the fuses tomorrow and test it.

[enblethen]

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]

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]

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]

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.