tachometer signal???

[sciontcboy]

Any idea where to hook up an after market tachometer?? Which wire has the signal source??? please answer me back asap!

[navylife59]

You can only tag onto the tach signal off the Crank Angle Sensor at the ECM behind the glove box. I am not sure if it is a pulsed 5volt signal or not. The tach on the gauge cluster is driven directly by the ECM via CAN. I will send you more info later tonight.

[sciontcboy]

so behind the glove box...do you know what color the wire is??

[navylife59]

Sorry, I was exhausted yesterday. I will post this afternoon the diagrams.

[sciontcboy]

thats cool..thanks i couldnt find info anywhere...so you still in the navy? im in the army national guard, 3 years strong

[navylife59]

Navy flying the back end of the Navy's trash hauler....C-130T Hercules.
7 years in Aug.

The 1st pic is the pinout for 2005-2006 models. The pin 5 (marked "I") on the E4 connector.



The following pics are for 2007-up models. As you can see, the pinout for the Tach signal have not changed.




Added the pinout for the Speed Sensor. It has waveform similar to the Tach output. Both waveforms become shorter as engine speed/vehicle speed increases.





Official Scion wiring color codes straight from the 2007 Tech Manual

[sciontcboy]

so its pin 5 on the e4 connecter??

[sciontcboy]

ok i got my glove box out and tried the wires...none of them gave a good reading. and i only have 4 plugs into my ecm instead of 5? and the colors were off? any suggestions??

[navylife59]

Pin 5 of Connector E4 is correct. Look at the shape of the connector to identify. What year tC? Also, the signal is 5VDC pulsed. A regular multimeter can't read that. What is the brand of tach your using Call their tech department and ask if the tach generator input is with a 5VDC pulsed signal.

[sciontcboy]

2007...i will try that thanks

[navylife59]

Originally Posted by navylife59

Call their tech department and ask if the tach generator input is with a 5VDC pulsed signal.

Meant to say, "call their tech department and see if their tach generator input is compatible with a 5VDC pulsed signal".

All the info I posted was straight out of the 2007 Scion tC manual.

[sciontcboy]

pin 2 on the e5 connecter is what is was in my car. its a solid black wire. thanks for the help and the diagrams!!! any idea how to get a wire diagram for the speakers on a stock 07 tc radio??

[navylife59]

What specifically do you want to look at? If you are wantign to add an aftermarket head unit then I STRONGLY suggest that you spend the $15 -$20 extra for a Metra radio harness. Never cut what you can plug into. Other caveats are that it is a cinch to install, not to mention, easy to replace the OEM at a later date. If some arse wants to steal your radio, he might just be nice enough to unplug it, instead of, ripping out all you wiring!