Techstream cannot communicate and "Handshake" with RES EC...

Q: Techstream cannot communicate and "Handshake" with RES ECU for 2015 Toyota Venza w/smart key. Help.

asked by on July 12, 2017

I have a 2015 Toyota Venza w/smart key. I've installed a factory remote engine start in my car. I cannot get Techstream (not Techstream lite) to communicate or "handshake" with the RES ECU. What am I doing wrong? Please help. Any advice with pictures to show would be greatly appreciated. Thanks a million.

My car has 10400 miles.
My car has an automatic transmission.

I would first refer to the unit LED Diagnostics and Troubleshooting in the installation instructions because it first has to be determined if there is a problem with the install (wiring issues, connections) or configuration. Also, you want to check for firmware updates both on the vehicle and in the unit in case that is an issue. The electrical installation of the RES system, both the component wiring and the order of operation, is very very detailed. So, in a situation like this, you do want to first verify that every single install detail has been covered and unit LED diagnostics might help. If, after all that, the Techstream is still not communicating, the recommended service is an electrical components diagnostic - vehicle programming and a certified mechanic would diagnose the issue for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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