When I bought new my 1999 RX I installed a trailer hitch and also the Toyota Trailering Wire Harness, p/n PT207-48980. Installation of the harness was not easy. Now I am transferring the hitch to a 2003 RX that I recently bought. Does this old wire harness work on the later year Gen1 RX? Or is there an easier solution? TIA.

 

Lexus/Toyota changed the harness and harness block on the RX300 several times between 1999 and 2003. Call your local dealer and ask for the part number of the harness/block for the 2003 and then look to see if its compatible with a 1999. If it is then the reverse will apply. The reason for the circuitous route is that they probably won't know if your old harness will fit the new car.