Getting a cable into the passenger area

Read your thread and thought of this...

Power through the Firewall (Gen 4) | PriusChat

Can't take the credit, but wish you good luck. Keep us all posted on your progress.

 

If your reason for running a cable thus is to get power, could you just find a 12 volt wire within the cabin, tap into it?

 

I believe all of the factory-installed wires that run between the engine compartment and the passenger compartment are part of the Engine Room Main Wire harness, which passes through the firewall in large, round grommets, in two places, which are different on LHD and RHD models. You can see the approximate locations if you look closely at the figures in the Location & Routing section of Toyota’s Electrical Wiring Diagram, available by subscription to techinfo.toyota.com or toyota-tech.eu. Be sure to click the Print button to get the PDF version of each figure, which you can save for later reference.

One word of caution: the Engine Room Main Wire is a very expensive part (in the U.S., the list price is $3,391.50). If the wire harness or grommets were to be damaged beyond convenient repair, replacement would be costly, not only for parts but also for the extensive disassembly and reassembly labor involved.

By the way, there are many different part numbers for the harness, depending on grade (trim level), options, and destination market, so I wouldn’t expect to find unused wires for options your car doesn’t have.

 

Sometimes I wonder whether a one size fits all approach wouldn't have been a better plan, if only for ease of maintenance costs.

 

It might depend on the cost of the copper wiring. I believe some older Corollas had the wiring for fog lights on models that did not have them.

 

Yeah, but let that against the cost for labor in rectifying or altering/modifying post delivery, particularly under warranty.

 

Here in the US we have ""port installed" options which are installed when the vehicle reaches the US.

When my son got his 2015 Prius v, he wanted remote start. Due to other requirements the dealer decided to order the vehicle from the factory. the smart salesman found that factory remote start was less expensive than the port installed option. He had initially quoted the more expensive one, IIRC and upgraded the price.