Hill Descent Control Plug in?

[jasunderland]

Going to drudge up an old post...

Any update??

[07-SV-650]

A few years late, but any news?

[Touchdown]

It doesn't make sense that the ecu would be programmed different. The easier way would be wiring harness connections.

I was just under the dash looking at the OBDii connections for the Volo12 and noticed that there are parts of the wiring harness that are not connected. I have an LE 4x4, so there aren't many options that should be unplugged except for the HDC.

If you think about it, there should be something plugged into the brake/brake master cylinder/etc that would help the ecu control the brakes. And maybe that is what was not plugged in and possibly the missing piece to what RacerZX needed for it to work.

If anyone with a SE-OR could look under there and take pics, I could compare it to what I see and possibly find a solution!

[07-SV-650]

Touchdown - I would think all the mechanical parts should be there since we have VDC, ABS, Auto Transmission, etc. It's my understanding that the HDC uses those systems we already have to slow the truck on a hill. I think you are right, we need someone with an Off Road model to compare with!

[disallow]

It has to be an extra module that attaches to the plug and interfaces with the BCM. The service manual doesn't seem to have any reference to it, must be model specific in the FSM.

[Touchdown]

A extra module makes sense, since I didn't see any place to actually plug in the open connectors. (Or they may just be out of view)

But since those connectors are right next to the brakes, I'd have to say that module/connector must be for the auto braking control.

[Frozen]

A extra module makes sense, since I didn't see any place to actually plug in the open connectors. (Or they may just be out of view)

But since those connectors are right next to the brakes, I'd have to say that module/connector must be for the auto braking control.

would you be able to tone or trace those wires and see if they go to the dash where the HDC switch would go?

[NVSteve]

If anyone with a SE-OR could look under there and take pics, I could compare it to what I see and possibly find a solution!

Gladly, but I need someone to post a pic showing what I need to be looking for/taking a picture of.

[rragpaoa]

I'm interested as well. Let us know what you find. However the ECU is an integral part of the overall system, and it may have to be programmed as well. But as an engineer, I would have left the programming of the HDC in the ECU across all models. There's no reason to leave it out.

[07-SV-650]

I've been perusing courtesyparts.com and have not seen any additional modules or anything, but than again, I don't know exactly what I am looking for.

[Touchdown]

OK here's a pic of the 2 open connectors (center and bottom right) that are taped to the OBDii plug wires. It's located below the dash on the gas pedal side.


And here's a pic under the dash, just above the brake and gas pedals.


I'm wondering if someone (NVSteve ) could take a look under his dash and see if he has those 2 open connectors or are they plugged in somewhere. (maybe a seperate module)

I looked and couldn't see any place where the 2 connectors would connect to.

* This could be a total goose-egg, but might be worth a look at least! *

[NVSteve]

My wiring doesn't look the same. I do have one connector dangling, but that's what I hooked a TPMS reset tool to, so that connector can be scratched off the list. Here are some shots, for what it's worth:

[Touchdown]

Thanks NVSteve!
Great pics!

Right in the middle of your first pic, behind the black tape wrapped around the wiring and in front of the gray foam...it looks like the same connector (the 2nd one) that I have open as well.

Can you confirm that it's not connected to anything?

You can also see the brown, orange, red, green and black wires wrap around, just like mine.

Maybe it's just a fuse?
I believe there's only one fuse box under the hood...correct?
Gonna look tomorrow and see if I can find anything remotely labeled HDC!

[Lord Farquaad]

Stupid question here. So you guys buy the switch and then connect it to the harness. Right? For HDC to engage, the vehicle has to be in 4L and be running down a steep decline for the HDC to engage. If the incline is not steep enough and the vehicle is not "running away", it will not engage. It will also dis-engage if you touch the accelerator. Like I said, stupid question.

[disallow]

Thanks NVSteve!
Great pics!

Right in the middle of your first pic, behind the black tape wrapped around the wiring and in front of the gray foam...it looks like the same connector (the 2nd one) that I have open as well.

Can you confirm that it's not connected to anything?

You can also see the brown, orange, red, green and black wires wrap around, just like mine.

Maybe it's just a fuse?
I believe there's only one fuse box under the hood...correct?
Gonna look tomorrow and see if I can find anything remotely labeled HDC!

There are a couple of independent fuses under there, I found that out the hard way. Nissan put some inline fuses in for trailer lights, on wires running out of the BCM.