2007 toyota sienna car starter

You have a nice van.  Improperly installed remote starters can cause expensive repairs. 

It is best to use a Digital Multi Meter to locate and verify all connections.  Another place to get the Tach signal is at the OBD2 diagnostics connector under the drivers dash.  It is usually a Black wire ( but not always ) at Pin 9.  Verify this signal with a DMM set to 20V AC, Black lead to chassis ground and Red lead to the wire at Pin 9.  You should get a reading between 1 and 6 volts that rises slightly with RPMs.  Here is a picture of the OBD2 connector from a Yaris. (  The wire is at Pin 9 but not Black )

As a point of interest, the APS901C is a remote start system only and does not include keyless entry.  

Once remote started, the Toyota Sienna's factory FOB's are disabled and will not be able to unlock the doors. 

The 901 does unlock the doors also. By holding the single button down for 5 seconds it will pulse the BLACK/ blue whenever the RS is on, giving the owner a way to unlock without a key. We always connect this on cars that have an inactive remote when running.

Here is another, perhaps easier, place to get the Tach Signal......

Here are some pictures of the Tach wire in a 2005 Toyota Sienna.

This is the BLACK/ Orange Tach wire in the OBD2 connector.

Here is a picture of the ECM behind the glove box.

The Tach wire is in the top connector.  Here is a close-up.