Does anybody know if the 99 gs300 engine wire harness will work for an auto 02 is300 engine? Will it plug right into the ECM and work? Any help is appreciated.

 

I don't think it will because I was told by JeffTsai that I needed a '02-'05 harness, instead of the '01 IS300 harness, for my '02 GS300.

 

No the 2 harnesses have different pinouts. What you should be able to do is use your current harness on the IS motor. Basically strip the whole original harness off the IS motor and replace it with yours...then it should all plug into your stock GS3 ECU. All the connectors should be the same shape and also in the same place.

 

02gs/is300 have different ecm connectors than 01 down

 

Can’t u just cut and splice the wires?