Unlock BOTH front doors with single remote click

[Frozen E]

Yep, I did it. It's a small annoyance I decided to fix. From the factory you had to hit the unlock button on the remote twice to get the passenger side door to unlock. No more after this mod. Single click unlocks both front doors, yet the hatch will still require two pushes.

Be forewarned, this is a pain unless you're a contortionist. All the wires you need to get to are BEHIND the under dash fuse box. The plug you'll be dealing with is a green plug "M" with 12 wires in it.

If you're feeling behind the fuse box, along the right side you'll feel a square bump. Plug "M" is directly above that bump. The release is on the top side of the plug. Once you unplug it, there won't be much wiggle room either.

The wires you're going to be "modding" are 8 and 9.

The one coming out of pin M8 is a solid yellow wire and runs to the passenger side lock solenoid.

M9 has a yellow/green wire coming out of it and runs to the driver side solenoid.

Here's the plug. The wires you're going to be dealing with are the 3rd and 4th from the left. M8 is the 3rd wire, M9 is the 4th


Cut the solid yellow wire from M8 (passenger side}


Tap into the yellow/green wire next door (M9). I temporarily did it this way just to test my theory. Simply stripped and twisted the cut wire around the exposed part of M9. This is now more permanent with solder and electrical tape. But you can really see what I was doing like this though.


You can probably make this even easier by using wire taps to tap into the M9 wire without having to strip anything. They can be found at Home Depot for a couple bucks for 5 or 6 of 'em.



Anyway, I'll try to get more pics up tomorrow, including the schematic of how this circuit is wired and what I actually did to make it work. So far I'm happy as a clam.
Leave the cut M8 right where it is. It's not hurting anything.

[av911]

Nice write up!!

Is there a way to have the "second remote click" do something else? Like roll the windows down or something.

[BigAl205]

Very interesting. I wonder if patching in P16 would cause the hatch to unlock as well :cool:

[Frozen E]

Originally Posted by BigAl205

Very interesting. I wonder if patching in P16 would cause the hatch to unlock as well :cool:

It probably would. They're simple solenoids in very simple circuits. I was just tired of fumbling around under the dash.

[Yoda E SC]

Originally Posted by av911

Nice write up!!

Is there a way to have the "second remote click" do something else? Like roll the windows down or something.

Originally Posted by BigAl205

Very interesting. I wonder if patching in P16 would cause the hatch to unlock as well :cool:

if you tapped it on the the same lock wire it would in theory work i would just be a little concerned with how much you are now asking one circuit to provide current wise when it was originally being done by 2 (both rear doors are connected internally) might be fine though. if you did that then you could take one of the outputs and have it run anything that works on momentary pulse like a dei 530t, although you would have to run it thru a relay to convert it from + to - and to isolate it from the fusebox normally resting at -.

[ramblerdan]

Cool beans, Frozen E. I will gladly buy you a case of your beverage of choice!

Question: Why cut M8? What if you just tapped M8 and M9 together?

I'd rather have the rear hatch unlock than the passenger door, so will try it with that wire (P16, eh?) instead.

[Frozen E]

Originally Posted by ramblerdan

Question: Why cut M8? What if you just tapped M8 and M9 together?

You'd blow the 15A power door lock fuse under the hood as soon as you go to unlock. Ask me how I know. :D

[Snuffleupagus]

Originally Posted by Frozen E

Ask me how I know. :D

OK. How do you know?

[BigAl205]

Originally Posted by ramblerdan

Cool beans, Frozen E. I will gladly buy you a case of your beverage of choice!

Question: Why cut M8? What if you just tapped M8 and M9 together?

I'd rather have the rear hatch unlock than the passenger door, so will try it with that wire (P16, eh?) instead.

Looking at the schematic, both sides of the actuators are connected to the common contacts of relays inside the MCU. The normally open contact is connected to +12 and the normally closed contact is going to ground. At rest, both sides of the lock motors see ground. When an unlock impulse is sent to the driver door, relay #1 sends 12v to one side of the motor and the other side already sees ground thru relay #2. When the lock impulse is sent, relay#2 sends 12v to the other side of the motor which is now grounded thru relay #1.
The other two locks are using relay#3 on the unlock side of the motors and using relay#2 for the lock side. They work exactly the same except relay #3 only engages after 2 clicks of the remote.
YEL/GRN to relay #1(M9= driver door)
YEL/BLK to relay#2(M7= driver door)(P17=hatch)(M6=pass door)
YEL to relay #3 (M8 pass door)(P16 hatch)

If you simply tie the M8 to M9, whenever you double click to pop the trunk, you will be sending 12v directly to ground.

[Yoda E SC]

Originally Posted by BigAl205

Looking at the schematic, both sides of the actuators are connected to the common contacts of relays inside the MCU. The normally open contact is connected to +12 and the normally closed contact is going to ground. At rest, both sides of the lock motors see ground. When an unlock impulse is sent to the driver door, relay #1 sends 12v to one side of the motor and the other side already sees ground thru relay #2. When the lock impulse is sent, relay#2 sends 12v to the other side of the motor which is now grounded thru relay #1.
The other two locks are using relay#3 on the unlock side of the motors and using relay#2 for the lock side. They work exactly the same except relay #3 only engages after 2 clicks of the remote.
YEL/GRN to relay #1(M9= driver door)
YEL/BLK to relay#2(M7= driver door)(P17=hatch)(M6=pass door)
YEL to relay #3 (M8 pass door)(P16 hatch)

If you simply tie the M8 to M9, whenever you double click to pop the trunk, you will be sending 12v directly to ground.

you got there before i had a chance....