What purpose for the toggle switch under the deck??

Take the parking brake wire from the deck and hook it to a toggle switch on the end of that switch run a switch to a ground. When powering up toggle the switch on and off and your in business

***DISCLAIMER*** The parking break switch in your in-car video player is a safety feature that is required by law, bypassing or disabling this switch is NOT recommended by any means. The answer I am providing is for informational purposes, neither fixya or myself are responsible for any consequences of the use of the information herein.
there are two ways to do this, there are marketed products designed to do this that come with a few parts and an instructional dvd. Or you may purchase simply a toggle switch, and some wire, and do the following.
There is a wire connected from the back of the dvd player deck to the parking break indicator bulb or wire on the dashboard (the light that comes on when your parking break is on). This wire can be disconnected from the parking break lamp and attached to a toggle switch, and then to a power source (12v+). With most manufacturers there is a "code" to enable video. Generally it's something to the effect "turn the parking break on for 1 second, off for one second, and then back on, and leave it on". Whatever the code is for your unit, you may now do the same with your switch to activate video.

The PTO switch has failed. There is an internal spring and plastic parts in toggle switches that keep them in the actuated position. It's not practical to take the switch apart to fix it, but replacement switches are readily available - probably $12 - $20. It's a good idea to disconnect the negative terminal from the battery before you do any electrical work. Be sure to put the wires on the corresponding terminals of the new switch. Good luck! Please rate if you find this helpful, thanks.

you dont need to run the parking wire just put in toggle switch and run red wire from toggle switch to skinny yellowish or greenish wire not the speaker wire and run the black from toggle to black ground from car and deck and flick the switch and watch whatever you want when u drive

just buy a toggle switch and put red wire to skinny yellow wire to your deck and black wire from toggle switchto black ground from car and deck flick the switch and watch dvds while driveing

you can by-pass it just buy a toggle switch and put the red wire from the toggle switch on the skinny yellow wire from your deck and put the black wire from toggle switch to your black ground from your deck and car wires and flick it and watch dvds while driving

Hi Dave
No ....go to a hardware store buy a toggle switch than get a single speaker wire (small wire) attach it to the red wire on the back of your pioneer deck (make sure to leave the red wire in back of deck as well) and attach it to the power on the toggle switch do the same with the black wire (ground wire) the black wire will go into the toggle switch under the power wire. finally install the parking break wire from the pioneer unit to the last slot on toggle switch and this should do the trick if not swap the ground spot for the brake spot on toggle switch >>>> MAKE SURE THE TOGGEL SWITCH HAS 3 HOOK UPS to do this correctly (your system will provide sound with the toggle switch off (Blue Screen) but when toggle switch is on you get video while driving) good luck

Hi There
buy a toggle switch with 3pin
use small speaker wire attach it to red wire on unit (make sure to not UN hook red wire just add long enough speaker piece to red wire) attach it to toggle switch top (power logo) do the same for the black wire (ground) only put it in the ground on toggle switch (ground logo) attach the brake wire to the last open toggle switch turn it on and video appears while driving (follow logos on toggle switch) if this doesn't work switch the black and parking brake wires around on toggle switch
hope this helped

buy a toggle switch
run a wire from the red wire located at the back of deck
to the deck and toggle switch (power to power on toggle switch)
do the same with the ground wire (black) (ground to ground on toggle switch) (make sure to follow logos on toggle switch)
finally install e brake wire to center pin on toggle switch
now you can watch make sure toggle switch is on
if this didn't work switch the e brake wire and black wire on toggle switch
good luck hope i helped

Most likely the part is the Valet switch, it is part of an aftermarket alarm that may have been removed, that is the most common place they are mounted.