2zz Swap on Vitz/Yaris SCP90

[blindmanwatching]

Originally Posted by CTScott

Did you get your hands on the wiring diagrams for the car that you grabbed the ECM from?

There are numurous wiring diagrams available online, for the 2001 celica, but I cant understand the whole concept of how the ECM is wired to the OBD2 plug. Need help with that.

[blindmanwatching]

Updates:

Got the cooling system sorted out. Initially there was no thermostat installed and the temperature sensor was not plugged to keep the fans running at all times. Now 82C thermostat has been installed and temperature sensor has been plugged back on. As a result the LIFT is working perfectly now and the car accelerates like crazy when LIFT hits.(Video coming soon)

AC condenser has also been installed. But having problem with the AC compressor. The 1KR compressor which was fitted on this 2zz has cracked . probably the reason being the smaller pulley size. And i cant install the original compressor because there is no room for a larger pulley. Someone advise?

[CTScott]

Originally Posted by blindmanwatching

There are numurous wiring diagrams available online, for the 2001 celica, but I cant understand the whole concept of how the ECM is wired to the OBD2 plug. Need help with that.

Wiring to the OBD plug is typically very trivial. That vintage is ISO9141, so there is one (K line) wire that is the communications wire.

Pin 16 is constant 12 V power
Pin 4 and 5 are grounds
Pin 7 is SIL, which is a direct connection to the ECM
Pin 13 is TC, which is a direct connection to the ECM

An OBDII reader communicates with the ECM via pin 7, which is the "K Line". For a standard OBD reader, just 4,5,7 and 16 are needed. Pin 13 is a toyota specific diagnostic wire.

[blindmanwatching]

Originally Posted by CTScott

Wiring to the OBD plug is typically very trivial. That vintage is ISO9141, so there is one (K line) wire that is the communications wire.

Pin 16 is constant 12 V power
Pin 4 and 5 are grounds
Pin 7 is SIL, which is a direct connection to the ECM
Pin 13 is TC, which is a direct connection to the ECM

An OBDII reader communicates with the ECM via pin 7, which is the "K Line". For a standard OBD reader, just 4,5,7 and 16 are needed. Pin 13 is a toyota specific diagnostic wire.

Thanks for the response.but on the ECM end, where will all these wires be connected? or will only pin 7 be connected to one of the pins on the ECM?

[CTScott]

Originally Posted by blindmanwatching

Thanks for the response.but on the ECM end, where will all these wires be connected? or will only pin 7 be connected to one of the pins on the ECM?

7 and 13 are the only ones that connect directly to the ECM.

[blindmanwatching]

Originally Posted by CTScott

7 and 13 are the only ones that connect directly to the ECM.

Ok. And are there any connections to the different sensors of the car...or does pin 7 and 13 provide all the data from the ECM to OBD2?

[CTScott]

Originally Posted by blindmanwatching

Ok. And are there any connections to the different sensors of the car...or does pin 7 and 13 provide all the data from the ECM to OBD2?

With ODBII the diagnostic tool just talks to the ECM and the ECM does all of the talking to the sensors.