Factory trailer plug not wired correctly?

[banerjek]

When attaching the trailer plug to my cabover, the trickle charge through the 7 pin connector didn't seem to be working correctly. So I pulled out a multimeter and did not get the readings I expected.

Viewed from my perspective (i.e. looking at the truck from the rear), I seem to get ground at the 1 o'clock position and positive at 5. Right turn signal is 9 oclock and left is 3. In other words, some stuff is opposite what I would expect. Testing from the truck camper side, I was getting positive and ground where expected.

However, I assume everything is done with harnesses that make it virtually impossible for them to get it wrong. Given that I don't know anything about this stuff beyond what I learned in a couple internet searches, I wanted to get a reality check before taking it in. Am I out of my mind, or is it possible they really did get it that far off?

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[P. A. Schilke]

Hi Kyle,

Does this help?

Best,
Phil Schilke
Ranger Vehicle Engineering
Ford Motor Co. Retired

 

[banerjek]

Your diagram corresponds with exactly what I expected -- but am not seeing on the truck side. Sounds like I need to have them look at it.

Hi Kyle,

Does this help?

Best,
Phil Schilke
Ranger Vehicle Engineering
Ford Motor Co. Retired

 

[Big Blue]

Hi Kyle,

Does this help?

Best,
Phil Schilke
Ranger Vehicle Engineering
Ford Motor Co. Retired

You need to be careful and take note of the key position in the receptacle on the truck. It is mounted what some people consider upside down. I never worry about it, just make sure the locating key lines up. Also you will not get voltage on the 12 volt lead unless the trailer is plugged in and the truck is running. I think it is part of the battery management system, to keep from draining battery.


BTW, my camper hooks up without issue.

 

[geophb]

Went through this on mine, trying to charge low camper batt at the campground. Went through fuses and everything, all a pain to get to. Turns out it was operating as intended.

The truck will NOT send 12v (charge/camper batt power ect) until it recognizes that a trailer is connected and pops up on the dash with all the trailer stuff.
Mine had to be put in gear with truck running before anything popped up, sometimes it would do it before going in gear though.

 

[banerjek]

Went through this on mine, trying to charge low camper batt at the campground. Went through fuses and everything, all a pain to get to. Turns out it was operating as intended.

The truck will NOT send 12v (charge/camper batt power ect) until it recognizes that a trailer is connected and pops up on the dash with all the trailer stuff.
Mine had to be put in gear with truck running before anything popped up, sometimes it would do it before going in gear though.

This is totally consistent with what I'm seeing with the proviso is that I am getting voltage on the lights, reverse, etc. Do I need to do something at the dash end to make it recognize, or should simply plugging it in work?

 

[geophb]

This is totally consistent with what I'm seeing with the proviso is that I am getting voltage on the lights, reverse, etc. Do I need to do something at the dash end to make it recognize, or should simply plugging it in work?

Start truck, plug in trailer then put in gear like your driving off and the dash should light up like a christmas tree with all kinds of trailer messages.
Then check with voltmeter and you should be good, assuming proper batt/wiring on the trailer side.

 

[banerjek]

Start truck, plug in trailer then put in gear like your driving off and the dash should light up like a christmas tree with all kinds of trailer messages.
Then check with voltmeter and you should be good, assuming proper batt/wiring on the trailer side.

Ahh, this I definitely never get -- didn't even know there should be trailer messages. However, gems on the cabover light up as expected and voltmeter shows 12V when flashing turn signals, brakes ae lit, putting in reverse, etc. However, no voltage where it should be hot. I do have voltage on the trailer side where expected. If it needs to detect something, that sounds like my problem.

 

[Big Blue]

Ahh, this I definitely never get -- didn't even know there should be trailer messages. However, gems on the cabover light up as expected and voltmeter shows 12V when flashing turn signals, brakes ae lit, putting in reverse, etc. However, no voltage where it should be hot. I do have voltage on the trailer side where expected. If it needs to detect something, that sounds like my problem.

I think I might be seeing the issue here. You have a cabover camper mounted on your truck, correct? Are you plugging the trailer into the truck or a connector on the cabover? How I the cabover wired into the Truck? The tie in of the cabover may be affecting the trailer detection and the 12v feed.

 

[banerjek]

I think I might be seeing the issue here. You have a cabover camper mounted on your truck, correct? Are you plugging the trailer into the truck or a connector on the cabover? How I the cabover wired into the Truck? The tie in of the cabover may be affecting the trailer detection and the 12v feed.

I have a cabover with a 7 pin connector that plugs into the truck. The cabover does have voltage and ground where expected. However, it appears the smart connector doesn't think I have a trailer which I don't, but I still want the voltage supplied when I run the engine.

I tried sitting in and out of gear with the brake pedal pressed to try to trigger it, but no luck.

Seems like there should be a slick way to change this behavior. In a worst case scenario, I suppose I could tap into a circuit that only runs when the engine is running (e.g. maybe headlights) to prevent the regular battery from being drained when parked, but I'd like to avoid a weird hacky solution.

 

[Big Blue]

I have a cabover with a 7 pin connector that plugs into the truck. The cabover does have voltage and ground where expected. However, it appears the smart connector doesn't think I have a trailer which I don't, but I still want the voltage supplied when I run the engine.

I tried sitting in and out of gear with the brake pedal pressed to try to trigger it, but no luck.

Seems like there should be a slick way to change this behavior. In a worst case scenario, I suppose I could tap into a circuit that only runs when the engine is running (e.g. maybe headlights) to prevent the regular battery from being drained when parked, but I'd like to avoid a weird hacky solution.

One more question, your truck does have the factory tow package with the OEM 7 pin socket correct? If it did not, it may not have the OEM trailer module. Normally if anything is plugged into either the 4 or 7 pin connector, even a light bar. The truck will sense it as a trailer connected. It then turns off BLIS (blind spot sensing) until a trailer length is entered, rear parking sensors and cross traffic warning.

 

[banerjek]

One more question, your truck does have the factory tow package with the OEM 7 pin socket correct? If it did not, it may not have the OEM trailer module. Normally if anything is plugged into either the 4 or 7 pin connector, even a light bar. The truck will sense it as a trailer connected. It then turns off BLIS (blind spot sensing) until a trailer length is entered, rear parking sensors and cross traffic warning.

It does have the factory tow package with the OEM 7 pin socket. It also has the trailer module -- for example, I can engage the trailer sway option in the dash.

It occurs to me that one way I could potentially solve my problem is simply rerouting the running lights to battery since those get 12V when they're on -- I don't care if the gems are lit, I don't mind driving with lights on, and it's simple swap. Another option I'm contemplating is putting a fake load on the brake lines since that's apparently what causes the smart connector to think something is there.

I feel like this is something someone else probably has a real slick way of doing. I need to take it in for some warranty work, so maybe there's a trick they can do with a jumper or something.

 

[Big Blue]

It does have the factory tow package with the OEM 7 pin socket. It also has the trailer module -- for example, I can engage the trailer sway option in the dash.

It occurs to me that one way I could potentially solve my problem is simply rerouting the running lights to battery since those get 12V when they're on -- I don't care if the gems are lit, I don't mind driving with lights on, and it's simple swap. Another option I'm contemplating is putting a fake load on the brake lines since that's apparently what causes the smart connector to think something is there.

I feel like this is something someone else probably has a real slick way of doing. I need to take it in for some warranty work, so maybe there's a trick they can do with a jumper or something.

Taking in is probably best place to start. Your the first person I've seen with a cabover on a Ranger. These things have so much intelligence on them, but we always find ways to fool then.

 

[myothercarizahearse]

sorry to hijack... what camper did you have?


back on topic- I'm assuming you have a charge controller in your camper. think about running heavier gauge wire direct from the main battery with water proof disconnects?

When attaching the trailer plug to my cabover, the trickle charge through the 7 pin connector didn't seem to be working correctly. So I pulled out a multimeter and did not get the readings I expected.

Viewed from my perspective (i.e. looking at the truck from the rear), I seem to get ground at the 1 o'clock position and positive at 5. Right turn signal is 9 oclock and left is 3. In other words, some stuff is opposite what I would expect. Testing from the truck camper side, I was getting positive and ground where expected.

However, I assume everything is done with harnesses that make it virtually impossible for them to get it wrong. Given that I don't know anything about this stuff beyond what I learned in a couple internet searches, I wanted to get a reality check before taking it in. Am I out of my mind, or is it possible they really did get it that far off?

 

[banerjek]

sorry to hijack... what camper did you have?


back on topic- I'm assuming you have a charge controller in your camper. think about running heavier gauge wire direct from the main battery with water proof disconnects?

I have a Capri Retreat. I could run a wire directly but was trying to avoid doing that just to keep things simpler. Also, I want to avoid setups that can drain the main battery if I don't pay attention to what I'm doing.

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