Jowie

Why not find a trigger for your buzzer from the stock keyless entry system instead of the power tap for the locks? That way, it would only beep when pushing the button on the remote, and not from the interior lock switches...

Just an idea...

djct_watt

I did this with a Lexus, and since 99% of Toyota harnesses are alike, I'd imagine it to be the same.

I don't recall which wire it was, but there is a set of lock/unlock wires in that harness (I forget if they are ground switched or positive switched). There is also a seperate set of arm/disarm wires (for the OEM alarm). These wires will also lock/unlock the car, but will arm/disarm the alarm as well. The difference is that one set sets off the locks and locks only (like when you have the key in the ignition) and the other set is linked to your key fob and the key hole in the door. This is why hitting the lock/unlock from inside the car sets the alarm off when the alarm is armed.

If you find the wires (by trial and error, or by looking at the wire harness diagram), it makes it a lot less painless. It's kinda annoying to honk your horn every time you hit the power lock switch. Furthermore, this is a good way to piggyback an alarm if you want to keep your OEM alarm. Using this method you can use an aftermarket alarm to arm your OEM alarm as a back up.

The reason I know this is because I had an alarm professionaly installed, and the baffoons at the shop told me it can't be done. Well it can. . . I rewired it to work on an LS400 and an ES300 (which mechanically IS a Camry). I'm fairly certain that you can do it on the tC.

Fhe1079

I'm still working on that too.... may take a while. Since the wireless receiver is behind the drivers side cup holders it makes it tough for a DIV'er.

jonnyHKboi

nice!...thanks for the write up!

djct_watt

You shouldn't need to tap into the keyles entry system. . . there is an amr/disarm wire set somewhere in the dash harnesses. It's the same set that are used when you use your key in the door to lock/unlock (which will disarm/arm the alarm). Read my post above.

jOhNL45b

nice write up man thanks...got a new summer project to work on

monkeyMojo

Has anyone discovered this yet? I would love to do this mod but a horn beep on pressign the lock button would be annoying after about a day..

I was thinking if this idea didnt pan out one could wire up a relay to only allow the signal to be sent if the door lock is pushed when the car is off (when acc line has no load?)..

djct_watt

That would work as well, but like I said, there should already be a set that does just that. I made a larger post above it, but it kinda went ignored. . . (people apparently don't like to READ).

Fhe1079

lol... i read it...

Have to check the wires first

monkeyMojo

I said that only as a backup to there not being arm/disarm wires available.

djct_watt

I FOUND IT!!!!!!!!!!!

Ok, all you tC guys who yell at us xA and xB guys who troll your forums, thank us NOW!

Courtesy of the12volt.com, I found the proper wires to tap. According to their install bay, find the 20 pin plug in the driver's kick panel.

Pin 14 (disarm/unlock) and Pin 15 (arm/lock) are what you'll want to tap. Keep in mind that these are NEGATIVE (ground) triggers. So that means that when you hit arm/disarm, the corresponding pin will connect to ground.

Before tapping anything, do a test to be sure the info is correct. Try grounding Pin 14 while the alarm is armed and check to see if the alarm goes off or not. If the car unlocks without a sound, you are good to go. Also verify that Pin 15 does the opposite.

Ideally you use a relay, but you can wire them up directly if you like. If you decide to use your horn, you will be jumping pins 14 and 15 together with the white wire in the steering column. USE A DIODE (buy it for a couple cents at Radio Shack). You will need the proper rating and voltage for it.
Why? You don't want someone to honk your horn and disarm your alarm, do you? A diode restricts electricity to only flow in one direction. You'll need a diode on the jumping cable. If you can't deal with Radio Shack, use a 12 volt LED. . . it's the same thing. Install it so that it DOESN'T work when you honk your horn.H
Ideally you use a piezo, and you use these pins to ground the circuit (or better yet use a relay).

I'm too lazy to do a complete DIY, furthermore, I have an xA and not a tC, so I can't verify or take pics. It CAN be done. There is enough info here to do it.

Enjoy.

Oh and:

Pin 14: "Purple to Pink" so it says. . .
Pin 15: "Green to blue" . . .

And just in case you guys need it:

DIRECTWIRE™ WIRING INFORMATION - SCION / tC / 2005 / Remote Start

[PRINT THIS PAGE]

12volts red (30A), white (25A) + ignition harness
Starter black + ignition harness
Second Starter green + ignition harness
Ignition blue + ignition harness
Second Ignition yellow + ignition harness
Third Ignition N/A
Accessory gray + ignition harness
Second Accessory N/A
Keysense black - ignition harness
Notes: Using the status output to trigger this wire during remote start will disarm the factory alarm without unlocking the doors.
Power Lock green to blue - driver kick, 20 pin plug, pin 15
Notes: Meter this wire while turning the key in the driver door key cylinder.
Power Unlock purple to pink (double pulse) - driver kick, 20 pin plug, pin 14
Notes: Meter this wire while turning the key in the driver door key cylinder.

Can also use the passenger door key cylinder wire for unlock, which only requires a single pulse. It is purple to lt. green (-) in the passenger kick, 10 pin plug, pin 7.
Lock Motor blue to brown 5wi driver kick, gray 7 pin plug, pin 6
Unlock Motor pink to blue 5wi driver kick, gray 7 pin plug, pin 5
Parking Lights+ brown + top of fuse box, 30 pin plug, pin 29
Parking Lights- brown - headlight switch
Hazards orange - hazard switch
Turn Signal(L) yellow + top of fuse box, 30 pin plug, pin 27
Turn Signal(R) green + top of fuse box, 30 pin plug, pin 28
Reverse Light pink + top of fuse box, 14 pin plug, pin 2
Door Trigger orange (D), blue (P) - top of fuse box
Notes: The driver door is orange in a 30 pin plug, pin 21. The passenger door is blue in a 16 pin plug, pin 14. Use both wires and diode isolate each.
Dome Supervision blue - L side of fusebox, 6 pin plug, pin 2
Trunk/Hatch Pin purple - top of fuse box, 30 pin plug, pin 7
Hood Pin N/A
Trunk/Hatch Release orange - driver kick, gry 12 pin plug, pin 12
Notes: Meter this wire while using the back door opener switch on the hatch.
Power Sliding Door N/A
Factory Alarm Arm arms with lock
Factory Alarm Disarm disarms with unlock
Disarm No Unlock use key sense wire
Tachometer black ac data link conn. under dash, pin 9
Notes: The tach wire is also found at the ECM behind the glove box, top plug, pin 5.
Wait to start N/A
Brake Wire blue + brake pedal switch
Parking Brake black - parking brake switch
Horn Trigger white - steering column
Memory Seat 1 N/A
Memory Seat 2 N/A
Memory Seat 3 N/A
Immobilizer Bypass Module: Required: Yes Type: Transponder Part #: 556U or 555U
Notes: N/A

__________________

djct_watt

Ok, so I looked back though the DIY. . . doesn't change it much (excellent write up FHE1079!!!!). The only difference is the wires you will use.

He also uses the horn trigger at the fuse box. . . that's no different than tapping the wire at the steering column, and probably easier. I'd go that route.

There are various ways to ghetto rig this, but I'm not going to be responsible for someone starting a fire. Crimps, tape, and make shift wires will also do. . . but be a champ and do it right.

Let me know when one of you guys gets this to work.

djct_watt

And in case you have an xB/xA and want this mod,

You'll want:
1) Blue/white wire, 14 pin plug in the kick panel
2) Yellow/Black wire, same plug
3) Tap the horn at the fuse box.

a1racer

cool info to bad the company was to cheep to spend .05 cent's a car to make this happen from the factory.

Fhe1079

Ya beet me to it Sid... But thanks man.

Here is the plug he was talking about. (should be white) Its the one i moved out of the way the first time.

O5_TRD_tC

it is the same color wires and #'s for the tC as well?

PghtC

could you mock up a pic?

I am following this thread so I can have it for future reference.

skrewCYCO

That's is kool... I've been thinking about that buzzer since i got my '05... neat... but i wan't the same buzzer sound as those on lexus' (like on the LX470) or other luxury cars... do you guys know what i'm talkin about? does that piezo have that sound? or any other brand you guys know/suggest?

PghtC

If wire 14 and 15 is a negative sense pulse, and the white wire of the horn is the negative, the diode would have to be facing the kick panel plug (silver side) and the black side facing the steering column. That will allow the diode to feed to the horn but not the other way. Correct?

djct_watt

I recommend using the fuse box relay as a place to tap the horn since you'd run a shorter wire, but yes, you are correct. Well, that depends on which direction you mean by "facing."

The best method? Test. Better yet, use an LED (light emitting DIODE). It's supposed to light up when you hit the remote (not the horn). An LED is foolproof, since you have visual verification that you've done it correctly. But if you are wiring smart, go for the cheaper plain jane diode.