Installing Trailer Wiring Harness on 2019 Toyota Highlander Hybrid

Question:

1 My understanding is that the hybrid vehicles 12 volt battery is in the back on the drivers side, not under the hood. 2 I think that I read somewhere in the owners manual that disconnecting the 12 volt battery can disrupt the vehicles functions, and should not be done because it will create startup issues with the hybrid system once it is reconnected.

asked by: Rod

Helpful Expert Reply:

It sounds like you're looking through the installation instructions for the Curt T-Connector Wiring Harness # C56217 that requires you to first disconnect the negative battery terminal.

You are right that on the 2019 Toyota Highlander Hybrid the 12V battery is located in the left-hand side of the luggage/cargo compartment. You are also correct that disconnecting and reconnecting the battery may at first prevent the hybrid system from re-starting. Keep in mind though that disconnecting the battery is what you have to do when recharging it as well.

If this happens after reconnecting the battery then you just have to shift the transmission into P (Park), open and close any of the doors, and restart the hybrid system (with the power switch in ACCESSORY mode. This will initialize the hybrid system again.

After disconnecting the battery the Curt T-Connector Harness is a completely plug-and-play installation using factory ports behind the interior trim panel in the cargo area.

expert reply by: Chris R