Speed Sensor Defeat Update

This thread can be difficult to understand because some posts are about the Bluetooth/telephone speed sensor defeat and some are about the NAV speed sensor defeat. Each is VERY different -- different connection to connect and different impact to operation. I did not do the telephone modification but the posts seem to suggest that the connection can be cut without significant impact to other functions (except the display of mileage bars and wheels turning) HOWEVER I did the NAV modification on my 2008 and it requires the installation of a switch because the NAV will not work without the connection. There appears to be plenty of options for installing a switch -- I put a push/toggle switch on the left wall inside the upper glove box. When we need to do anything with NAV while moving -- we just pop the glove box, press the switch, make the entries/selections and then press the switch again. Works wonderfully...is out of sight and was easy to install.

 

I certainly agree with that. It really would be nice to have the cars system automatically connect to the phones directory the way my Garmin Nuvi does without transfering the phone book to the cars system at all. I do admire those of you who are willing to modify the cars system. At one time I would have jumped right in and tried it also, but now as I am getting older, I am not quite as brave as I used to be.

 

Thanks for the reply! Based on your feedback, I installed two switches for the overrides. This works very very well. I think this is much safer than fiddling with the phone, and much better for nav changes.

One thing I noticed on my BT override is that the instantaneous mpg readout still works. The only functionality loss I see is the bars on the Consumption screen.

This is good to know. I tried a few things on my drive home last night, and didn't run into a situation where the secondary lockout kicked in. I don't remember the longest amount of time that I left the override on, but I was certainly able to do the things I needed to do.

 

I assume you all know that the BT still works while moving if you use the voice commands? On my 2008, I can call any number that I can remember by using the voice system while the car is moving. It would be better to not have functions disabled but voice is a work around.

Also, for any of you that would like to be able to find most numbers for free, call 800 FREE 411 from any landline or cell phone. You get a 10-second ad and then free directory assistance.

 

That is the issue. You have to know the number. I agree that the voice dial works very well. Also, using voice for entering an address is best when driving. However, having access to my phone book on the big screen for numbers I don't know is the safest/quickest route, and being able to reorder an itinerary or put in a POI by name is fantastic.

 

Thanks for posting this good info although im having trouble figuring out which wires you are talking about could you post some pictures? :bowl:

 

Does my page help?
Prius Speed Wire

 

I'd like to know the difference(s) between the BT mod provided here (cutting the speed sensor wire) and the one sold by Coastal.

Thanks.

 

Since some people asked ... a user named Brosnan posted some circuit diagrams back in 2004, but subsequent upgrades of Priuschat.com caused them to disappear.

You can see them on the Internet Archive's Wayback machine at PriusChat.com :: View topic - Speed Sensor Defeat Update

All of them appear to be there except for the automatic dual-defeat schematic.

The slow-motion nav defeat looks interesting.

 

Bluetooth is in the phone you buy and the device you use. There is no "Bluetooth service" from any of the Carriers. If you buy a Bluetooth Phone and a Bluetooth car kit you can talk hands free using Bluetooth. My wife uses the Toyota Bluetook car kit that comes from the factory and when driving the functions are disabled. I use a Motorola B/T car kit and don't have the problem or the fancy screen to use either. Any way he can have B/T if he has the right phone and a car kit to match. Hope Wayne gets hot as we generally use the wifes car for long trips and it is a pain!

 

Thanks to all who've gone before, I've finally been able to install the BT defeat switch with relative ease.

I used this SPST switch from RadioShack. No need for soldering. Just used two flat F-connectors to connect my zip cord to the two poles on the switch. At the other end I used bullet connectors for the cut wire to make it easier to reconnect it later if needed.

I installed the switch between the SKS and Tire Sensor buttons to avoid having to drill any holes. The switch is a little wider than the precut hole, but nothing a sharp hobby knife couldn't rectify.

I also discovered that the panel removal tool is excellent for prying the A/C panel out. And it's helpful to open both upper and lower glovebox to give yourself more room to work.

Since my car doesn't have Nav, this is all I need. For a car with Nav, I'd imagine a DPST switch in that same location would do the trick very nicely.

I can't believe I hadn't done this mod earlier. My wife and I carpool and we take turn driving. This will make our driving experience a lot better (and safer too.)

 

I'm not quite sure what the point of the switch is? I just cut the speed wire ( left enough wire on either side to splice togehter when ready to sell) and left it like that. This way the phone, MP3 detail and FM message info is always on. Why is a switch needed to see 5' consumption bars and the wheels turn? Also, the install is much easier and faster - just pop off the center speaker grill and cut the wire. I don't mean this to sound like it's dumb to add a switch, I'm just not sure what it's for.

 

I suppose if you don't have Nav then a switch just for the BT is not as necessary.

For me, I prefer the ability to keep the original functionalities intact. If I need to take the car to the dealership for service, for instance, I don't want them to see that something is "wrong" with the car...

 

I think his car is 08 pkg 3, thus no Nav.

Oooh... I want, I want!!! Where to find info?

 

I also tried the speed sensor "cut wire" approach" for NAV freedom to program while driving. It works, but there are some draw backs. While you are progamming the NAV, the map stops updating your position as you drive along UNTIL you flick the switch back to recreate the factory mode. The longer you program you NAV while driving, the farther off your map will be from your actual location. One time, we had diven so far that the map was "lost" and was not able to figure out our current GPS location until we shut the car off for 30 minutes. If anybody has another explanation for our observations, please post ! THANKS

 

Here's the schematic of the BT speed sensor auto defeat in case anyone wants to build one: http://www.wb5mrn.com/prius/bt_only_schematic.jpg