Doing a head unit upgrade.,,Does anyone have the list of what the 4 white connectors are to the factory radio. Im pretty sure I know what 3 of them are....but at a loss what the 4th one is for?????
Sorry, haven't got those pinouts handy. Wiring diagram.... Toyota Service Information and Where To Find It | PriusChat
The only thing to consider is JBL wiring or not. If as you say it’s a basic radio then this (or something similar in your country) would be your friend. You need a Toyota to ISO adapter to install an aftermarket head unit. Toyota/Lexus/Daihatsu ISO Harness Adaptor - CT20TY01 | Halfords UK