[SOLVED] 2009 Mustang Installation Challenges

CuriousGeorge

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I appreciate anyone's help with this, I am almost at a loss. I might have to resort taking it to a professional.

The 2009 Mustang has 2 power ports. One on the dash, and the second is in the cubby storage in the center console between the front seats. Both are constantly on, even with key removed. They never shut off. Since they are both always hot I can't use the power adapter to power the A139 Pro, since it will never shut off.

I have therefore tried to hardwire it using the HK3-C, not because I want to use parking mode, but because I just want it to shut off when I turn the key off.

I have the complete wiring diagrams and schematics for this car. I can post copies of any diagram if this helps anyone with this puzzle.

There are 2 fuse boxes. Engine compartment and passenger side A-Pillar. I want to avoid using the fuse box in the engine compartment and drill a hole through the firewall as this car is notorious for water leaks in that area. I have been focused on tapping a fuse in the passenger compartment.

The passenger compartment only has 3 fuses that are "Always Hot".
F8, 10Amps Instrument cluster (IC), Datalink Center (DLC)
F10, 5 Amps HVAC Module, Overhead Console
F15, 10A Stop lamp Switch

My preference is a fuse tap on F15 for the red wire on the HK3-C since its not used for any major systems.

The passenger compartment has several fuses that are powered when the key is on, but only 3 are low risk, as the others are connected to major systems. I assume any of these 3 should work for the yellow wire on the HK3-C. More on that below.

F3 10A Blower Motor Relay, Windshield Wiper Motor
F7 10A Inside Mirror, Ambient LED lighting.
F13 is identified as NOT USED, but I found that it also is on powered on with the key.

This car, like many Ford's has a ACC Delay Relay. There are 2 fuses behind that relay. One would think this could be used for the yellow wire on the HK3-C, but sadly not.

F4 5A Exterior Rear View Mirrors
F6 5A Power window switches, and power door lock switches.


And here starts the challenge.

I found a good ground point, no issues there.

I used a fuse tap on F15 for the red wire since it's just the stop lamp.

Attached a fuse tap to F7 for the yellow wire.

Camera turns on, when key is turned. Camera turns off when the key is turned off. So far so good.

Everything else seems to work in the car.

When I use the key fob to lock the doors (there is no alarm) I can only unlock the doors within the next 10 or 15 seconds using the key fob. After that the key fob does nothing. I have to enter the car using the key, however the power door locks still work.

Same behavior exists if I use F3, F13, F4, and F5.

Everything else works when this issue happens, only issue is the keyless entry fails.

If I disconnect either the red or yellow wire tap, and reinstall the appropriate fuse, everything works fine again.

I tried using F10 for the Red wire, but that made the power windows stop working.

So then I decided to try a fuse tap from the engine compartment. I used F46 25A Horn Relay with a fuse tap to the red wire. This combination actually worked fine ai think. Everything so far seemed to work ok, as far as I could tell, and the keyless entry also worked fine. I used F13 in the passenger compartment for this experiment. Didn't try others since this seemed to work.

If this is the solution, how do I run a wire to the passenger compartment? The grommet that passes 50 wires through the firewall Is notorious for leaking, so I don't want to mess with that.

Has anyone installed the A139Pro into a 2008-2009 Mustang successfully? The power ports are not an option.

I am guessing this issue happens because the HK3-C has a small power draw as it continuously checks the condition of the battery, and the passenger Fuse box probably senses this and shuts off the keyless entry to prevent someone from breaking in. Completely assumption, but the schematics have not helped to make this any more logical than that.

I need a hard wire kit that does not have a cutoff, and simple attaches to ACC and ground for this to work.

Is there a hardwire kit for the A139Pro with only 2 wires (ground and ACC)? The hardwire need not check for battery voltage. Basically I'm try to recreate the behavior that an ACC power outlet would provide. I don't need parking mode to work, just simple on/off when I turn the key.
 
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Sorry that your Mustang's 12V power ports are always-on. For inspiration for another approach the 908ssp user from a Mustang board says they solved the problem (but did not post detailed follow-up instructions for others - grrr). I am not handy with electronics so I have no idea what this means... Only FYI.


908ssp: I did it without cutting or splicing any wires. Pretty much like I said in my first post. I found the fuse which is in the engine compartment and wired a relay in place of the fuse and triggered it with a ignition on wire also from the fuse block so I have the 20 amps available but only when the ignition is on.


908ssp: There is an unused fuse location in the fuse box under the dash on the passenger side panel. One is switched one is unswitched.
 
If I use something like this, and tap into an ACC fuse, then connect the USB cable supplied for the A139 Pro, would the A139Pro work?

DC Converter 12V 24V to 5V 6A 30W Dual USB Female DC DC Buck Converter Power Adapter Step Down Module https://a.co/d/4jlyoTS

I am doubtful as another member tried to use a non-Viofo USB C cable to power the A139Pro and would not even power on. Its not too expensive, so I'm gonna give it a try, along with any other suggestions or recommendations that you may have.
(No parking mode of course, at this point that's a compromise I'm willing to deal with.)
 
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Sorry that your Mustang's 12V power ports are always-on. For inspiration for another approach the 908ssp user from a Mustang board says they solved the problem (but did not post detailed follow-up instructions for others - grrr). I am not handy with electronics so I have no idea what this means... Only FYI.


908ssp: I did it without cutting or splicing any wires. Pretty much like I said in my first post. I found the fuse which is in the engine compartment and wired a relay in place of the fuse and triggered it with a ignition on wire also from the fuse block so I have the 20 amps available but only when the ignition is on.


908ssp: There is an unused fuse location in the fuse box under the dash on the passenger side panel. One is switched one is unswitched.
Thanks any inspiration helps.

Indeed I found the switched fuse F13 in the passenger compartment which is labeled as unused, read the same post on a Mustang forum, so that was a great lead. I think there is indeed another one I found that is always hot F5, F9, or F11(don't remember which one).

I'll have to try that again using one these 3 for the red wire (BAT)

I also read the article you posted about using a relay, but that means I need a place to mount and secure a new relay in the engine compartment. This might be beyond my capacity, but definitely something to consider if I decide to take it to a professional.

I really appreciate your reply though.
 
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There are 4 unused fuses. 2 are constant on(F9, F11) and 2 are switched(F5, F13).

I tried every combination. Only combination that turn on the camera was F13(yellow) and F9(red).

But with this combination the keyless entry again becomes unresponsive after a while.
 
On to plan D, hardwiring a new USB charging outlet....

I wanted it to switch off with the key, so I could only choose F13, or F5.

F13 did not turn on the camera when key was turned.

I tried F9 and F11, both powered the camera immediately. Although this was expected, however undesired I just wanted to try it.

I finally landed on F5(switched) and ground. Only has 2 wires of course.

This combination turns the camera on and off with the key, and it seems like the keyless entry works too. All other electronics seem to work as well.

I am not going to run the wires tonight nor have I taped the cameras to the glass yet. I want to test it for a few days.

I would consider this problem solved as long as you don't want parking mode enabled in a 2008-2009 Ford Mustang.
 
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