Tilt sensor

Now I need to see if the NA version of the gen2 has the low and high horn, and if the security horn is on the firewall.

 

I got a shock sensor installed yesterday.

Used these links
DIY: Car Modz on youtube -

Dong Tu on youtube -

Dong Tu youtube has some videos where he installed a tilt sensor, he had issues with them burning out, but his more recent video he goes over what was happening and how he fixed it. I think this is the most recent. Here's the link

I used a relay like in DIY:Car mods vid, 2 add-a-fuse , t-tapped to the purple wire coming from the driver side door switch. Important to remember that when testing the alarm, make sure to wait around 1min for car alarm to arm.

 

Dong wires this with shock sensor but what if I’m just wiring tilt sensor? I don’t want to fry my unit. So red goes to constant 12v, orange goes to ignition 12v and blue goes to door plunger cable? Do I need a diode or ground it somewhere?

 

Successful install. Lost one catalytic to thieves about a year ago in front of my house!. I added a cat protector plate, but to minimize the chance of another thief jacking up the car, I followed the Dong Tu videos. He ended up following another video by 12 volt neutron which is actually very good but Dong specifically installs on a Prius. I also got the DEI 504K shock sensor which makes the wiring hookup a little more logical if you follow the videos. The only issue I had is dealing with tapping into the sensor wiring which is extremely small diameter (very high wire gauge, I would guess around a 22 or 24 gauge or maybe higher, and all my tools would not work correctly for that size electrical wire. I eventually got it connected and it works correctly but if I could of found an alarm shop to do the install it would have been faster. All the shops I contacted wanted to sell me a complete alarm system, which means my car would end up having two key fobs/remotes and I didn't want the additional cost of a complete system.

 

Are there pictures or videos anywhere showing the final install with everything buttoned back up? The Dong Tu videos I have seen so far show everything torn apart, which isn't how one would leave the car.

Also, what sort of taps are best for the 3 wires (and what are the actual gauges of the car loom and sensor wires)? DT used some sort of T tap but I am not fond of those for small wires as the blade which goes through the insulation can eventually cut through all the thin strands and cause an outright failure or intermittent problems. If they are to be used it is important that they be sized for the wire.

 

Something wrong with that picture - the wipers are backwards, at least with respect to my 2007. The fuse box is in the right place though. I looked where it shows the alarm horn and didn't see anything, but maybe it is down too low on the firewall to see from the top?

 

That attachment is showing the RHD layout. You should note the poster's location is UK.

 

Ok, if that is the right hand driver layout wouldn't that put the security horn right where the steering column comes through?
I have searched for quite a while for a picture which showed the actual location but came up empty. Maybe it isn't on the firewall but is mounted further into the engine compartment. There is really no way to tell how far forward it is from that drawing. The manual section which describes how to remove the security horn says "remove the security horn", which was remarkably unhelpful as instructions go!

This is a different model Toyota, but perhaps it gives a clue?

The security horn shown in parts catalogs looks very much like the one on the inside of the plastic case in that video.

 

I'm researching parts now to add the tilt sensor. Before ordering those some measurements of the electrical characteristics of the door open switch system were in order.

Unscrewed both of the back door switches but there was not enough slack on either to pull the switch out far enough to unplug it and gain access to the wires. Here's hoping they never fail, because parts of the interior are going to have to come off to replace them! Luckily there was just enough slack to pull the one on the front passenger door all the way out. Detached the plug from it and put a clothes pin on the plug so that it couldn't fall back into the body. With the switch off the single wire (odd color: somewhere between brown, orange, and red) had 11.89V on it. Short that to a ground and the dome light came on. Unshort it and about 15s later the light would go out. Put my DVM on the "10A" ammeter setting and shorted through it from the wire to ground. Measured 310 mA. The same current was measured with the dome light set to "door" or "off". So the pull up resistor (or whatever equivalent circuit is in there) is 38.4 ohms. The smallest resistor I had on hand was nominally 60 Ohm and measured 61 Ohm. Placed it between the wire and ground and measured 8.8V across it. That was not enough current (or voltage drop) to cause the dome light to come on. The sense line most likely needs to get below around 1V. 11.89 * 61/ (61+38.4) = 7.3V. So the car's circuit isn't acting like a pure drop resistor, but it isn't that far off either.

This does suggest why the 507M tilt sensors burn out when attached directly to the door wire. (See for instance Dung Tu's YouTube videos.) 310mA is quite a lot of current for what might be a very small transistor in the device. Initially I was going to use the 507M to drive an LCA110 solid state relay, whose output was wired in parallel with the door switch. I have used that part before and it is reliable. Also I have one in my parts bin. But it isn't rated for that much current. So something a little bit heftier will be needed. A mechanical relay would have a low enough resistance to pull that line all the way down, but I like the solid state devices better since there are no moving parts. An LCA701 should do, it has very low resistance on the load side when active. Also it can handle up to 2.5A so 300mA shouldn't be a problem for it.

 

Thanks for your video. It's very interesting, gives some good info. And it made me smile.

 

Any additional updates, or images worth sharing for your tilt sensor installation?

 

Nope, I have been busy with other things, but hope to get back to it soon.

I did mock up an alarm circuit on a breadboard that could pull enough current not to burn out when wired to the door. It triggered correctly with either the shock or tilt sensor. This was on a table, not in the car.

The 507M appears to behave differently than advertised. Reading what people have said gave me the impression that when the ignition line went low it "set" the current "vertical" vector and that tilts away from that would then trigger the signal line to go low. It is more complicated than that. For instance, it has to sit a while before it will respond to the 1 degree tilt. After that if it is tilted to let's say 5 degrees it will emit one pulse. If it then sits at that new position for a while it looks like that becomes the new "vertical", because tilting it back to the original position triggers another pulse. So what I think it may actually do is "settle into a new vertical" following the ignition line going low OR after any tilt event. Finally, the board is not held firmly in its case and can shift around. Since we are talking 1 degree tilt sensitivity, that is a bad thing. It should be stabilized with some hot glue or a shim or something like that. It is easy to open the plastic case, just pull it apart.

While I have not tested it, I think that it is possible the 507M might not ever respond to a significant tilt if the transition to the new orientation was made slowly enough.

 

Reminds me of an online review citing similar build quality for the "Directed Electronics" version of the 507M.

...The following day however I started getting false triggers and I know it's the tilt sensor because I wired it into the 2ed sensor port in my alarm so when I have a trigger it tells me which sensor was triggered. I have a feeling temperature fluctuations are the cause because I've noticed no false alarms when temp is constant but during a time of day where it goes up or down I get triggers.

I have a replacement on its way. I will update once installed. I'm sure it will be fine. Nothing is perfect.

Edit: I decided to look closer at the unit after removing it. I noticed that the white connecter was able to move around a lot inside the case. It took a minute to come back to me but I realized the case was put together backward. The screw mount hole was on the same end as the connecter. This leads me the believe this unit could be a return and repackage by viper not the seller. I want that last part to be very clear. The package was fully sealed in ani theft plastic...​

 

I am also installing the 507M Tilt sensor. I pondered for a while exactly where to locate it. The instructions suggest to affix it to the floor, but I wanted it more central, so I put it in the middle behind the dash (see photo) near the radio. At first, I tried to screw it down, using an existing hole, but managed to drop both the screw and nut down inside. So just used 3M double-sided tape and a zip-tie.

I've bench tested it -- it's extremely sensitive most of the time, but as others have noticed, if the angle is increased slowly, it doesn't seem to respond until the angle is decreased again. I've not yet got everything hooked up in the car, but hope to soon.

 

Buy a universal tilt sensor and fit it in parallel with your door switch that illuminated the interior light. when you tilt your car the which will make contact and it will activate the alarm.... and switch your interior lights on....

The tilt switch is like any other switch, except its switched on or off by tilting the switch (look for markings on it) So a little time and a about £5 will sort things out.

 

Newb here, did you just strip a section of the positive lead on the door pluger wire and wrap the sensor wire around that with electrical tape? Also, did you solder the grounding wire onto the section you pointed out in the picture?

I think I may install a kill switch for this sensor since I do park on hills a lot, that or I may mount it onto an adjustable tripod camera mount to level it each time I park (hacky, but functional).

 

can you advise how you connected the sensor? I tried a method described here Directed Electronics 507M Tilt Sensor Installation Instructions with Factory Alarm | PriusChat but it didn't work

 

Currently installing 507M tilt sensor (thanks to @mark010101 for the installation guide).

Plan was to also get a Catshield but they are really hard to come by here in Sweden, no local alternatives yet. Can I sleep easy with just the tilt sensor and the new converter with its "smartdna" theft protection, or do I need to do some DIY solution, maybe weld rebar along the exhaust system?

Also, how exactly are the thieves cutting the horn wires? Isn't there a third security horn as well? Has anyone found a workaround to stop the thieves from silencing the alarm?

 

Business opportunity to just start making and selling them there!

 

Update: everything wired up but the alarm doesn't work. Tried opening doors with the windows down and car locked; alarm doesn't sound.

Maybe my Prius never had a factory alarm? Come to think of it, I don't think I've ever heard it before.