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Premium Member
5,207 Posts
Discussion Starter · #1 ·
Thanks to member Technique for this tutorial.
This is a "add-on" DIY for those of you who have already done the nav hack. As we know, the nav hack does NOT enable destination entry while moving... Only mp3 folders while moving, bluetooth phone dialing while moving, and if you have ML, it also enables DVD watching while moving...

If you have V5.1 of the navigation DVD, you can use the override function hidden in the volume menu. But, this must be done every time you start your vehicle, and if you have V6.1, the override is hidden/gone, so that's not even an option (unless you use my hybrid disc method)...

But anyway, for those of you who want to be able to enter destinations while moving at the flip of a switch, this is the DIY for you...

Quick background:

The nav display and nav unit (brain) are two separate parts... Each one has a VSS (Vehicle Speed Signal) wire running to it telling them when the vehicle is moving... The standard nav hack cuts the VSS to the nav display, but leaves it running to the nav unit (brain)... This is why you still can't enter destinations while moving, because the nav unit (brain) knows the car is moving... If you cut VSS to the nav unit (brain) then the nav will not work properly because it is using ONLY GPS signals to calculate the vehicle position... So, my solution was to install a switch in between the VSS source and the nav unit (brain) so that when I want to enter destinations I just flip the switch, enter destinations, and when I'm done, flip it back...

So, in summary here's what the switch does:

1) Switch off - Vehicle is in normal operation, nav hack fully enabled, and VSS is reaching the nav unit (brain) - Smooth navigation, destination entry while moving NOT allowed

2) Switch on - VSS is cut, not reaching the nav unit (brain) - Navigation is jumpy/not accurate, destination entry while moving IS allowed

When you switch from on to off, the nav almost instantly becomes smooth again! Very nice...

On to the DIY:

First, cut/unconnect the pink wire that you connected to the silver/white wire (J50 pink wire, J1 silver/white wire) when you originally did the nav hack...

Get two long pieces of wire... Connect one of these pieces of wire to the Pink wire coming out of the loom that originally went to J50...

Next, take your other long piece of wire and connect it to the silver/white wire that originally came out of J1...

Here is my added black wire crimped to the white/silver wire:

So, I think you guys can see where this is going... If we were to connect the two extra wires we just added, the nav hack would be the same as it was before we started... So, run these wires back behind the dash and out from the driver's footwell... Then, connect both of these newly added wires to the switch as such:

So, just run these wires under the dash, tucked up and zip-tied... If you get down where the pedals are you can see up under the dash quite well and secure the wires there... I removed the plastic cover under the dash but I don't think you even need to do that, I just wanted to get a better view... It's not that bad at all...

Now, to mount the switch, I chose the dead switch/panel location to the left of the steering wheel... I removed the side instrument panel cover to get to the back of the 3 buttons (note, in this picture I have already removed the blank and ran the switch through:

You can barely squeeze the clips holding in the blank with some tools, which is what I did. The blank then comes out.

Here is a picture of the blank:

As you can see, you really can't "cut out" an area to mount a switch, unless the switch was TINY... And the plastic is VERY thick (.25") and hard, so it would be difficult to cut even if you could find a mini-rocker switch.

So, here is a picture of my instrument panel with the switch coming out. Unfortunately, the first rocker switch I bought was too small, I wrapped a rubber band around it so it doesn't fall through the cutout:

The Toyota switch I used (Toyota OEM Fog Light Switch) is NOT an exact fit in the slot where the blank used to be... The inner opening of the dash is not big enough as there are two small plastic bars on either side... So, I took out a handy file and filed them down smooth... The Toyota switch was then a perfect fit, and the blank was also still able to fit in there perfectly (if you ever wanted to return it to look like stock)...

It takes some skill and patience to file down the opening perfectly, but it's not that difficult...

UPDATE: This switch - Scion OEM Style Rocker Switch Appears to be a perfect fit, but no one has tried it yet... Either way, it doesn't have any markings (which I like better), so if anyone wants to do this hack, I'd recommend this switch...

Anyway, here is a picture of the files I used as well as the dash covered up with blank tape to prevent accidental scuffing while filing the inner hole:

The finished product:

Anyway, as usual, this is all on my website... Hope this helps some people who either don't have the software override functionality or who would prefer to have a switch...

One caveat: If you are traveling at high speeds (such as 55+ MPH on the highway) the system will eventually (after 1 minute or so) realize you are moving as it is receiving GPS coordinates... So, if you are at highway speeds and flip the switch, you'll have about 1 minute of time to enter your destination... Then it will be locked out again... But, all you have to do is flip the switch off and back on again and it will unlock... At slow speeds I think this only happens after 2-3 minutes, maybe longer... I've never taken long enough to enter a destination to find out...


What's all this, then?
166 Posts
OK, this is a nice summarization of adding the switch to the Nav Hack. The only thing that's missing (for folks that haven't attempted the "first part" of the hack) is...well, the first part.

There are several 500+ message threads on various forums that go over this hack that make my brain hurt when I try to read them. So, if I try to summarize the "first part" of the hack here, can somebody tell me if I'm correct?

In summary:

1) Cut the pink wire into connector J50.

2) Tape off or wirenut the J50 CONNECTOR-side of the pink remains unconnected.

3) Cut the white/silver wire into J1.

4) Tape off or wirenut the WIRE LOOM side of the white/silver remains unconnected.

5) Follow the rest of the hack as illustrated in the post/pictures.

Is that pretty much it?

One question...this post says that when the switch is "Off" (which I take to mean "open"), that the system is in normal operation. Isn't that really when the switch is "On" (which I take to mean as "closed"), such that the pink & white/silver wires are connected??

9 Posts
Two questions as I've been trying to finish up my DVD Nav hack and a PXAMG+HDRT install:

1. The white/silver wire mentioned to be on P1 ( on my car is black and white striped with a some silver rings. That is, the upper right-most wire (looking at the back of the DVD Nav). Is that the right wire?

2. After putting my car back together (verifying that the HDRT and PXAMG were working), I found that my Nav no longer works. When I push the Map button, I get a "The External System is not connected." message. Has anyone experienced this?

Also, for those with a PXAMG/HDRT, the system worked as I was putting the car back together, up to the point were I started adjusting the location of where I wanted the PXAMG and HDRT (putting it under the glove compartment. However, after setting the locations, I no longer got my "SAT" options (HD, iPod). I tried swapping PXAMG units and plugging/unplugging/replacing the PGHTY1 but still no SAT option.
Anyone have this issue as well?
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