"I just did this mod last night, to my 2011 SR5... One thing I did notice, though, is that even after the mod, when the Party Mode button is engaged/depressed and the rear side door speakers are turned off, the rear hatch speakers are boosted louder than when the Party Mode button is not engaged..."
Hi kdcold'
So glad to learn that you've implemented [MENTION=49162]Ryan_S[/MENTION]'s 'party mode' modification; it's not just a system upgrade, but (should be) a requirement! A while back I could no longer tolerate the poor sound quality of my 2012 4R limited's audio system so I analyzed Toyota's party mode function to understand how it worked so that I could fix it. Everything that Ryan says in his thread is 100% accurate; let there be no mistake about that.
When I modified my (non JBL) entune system, I went one step further though, to maintain the functionality of the rear passenger door speakers whether in party mode or not. In your post above you mentioned that your rear door speakers will still turn off w/party mode engaged. You also explained that your tailgate speakers would get
louder when in party mode; let me attempt to explain why this happens.
When you're
NOT in party mode (normal mode), all of your rear speakers are wired together
'in series' (8 ohms) with each other, so power distribution becomes equal to all of the driver components. When the party mode system is
ON, the wiring configuration is completely changed. The rear door speakers are disabled, forcing all of the amplifier's power towards the much lower impedance (4 ohm) tailgate speakers; so they become much louder than the 8 ohm combined circuit.
In order to fully exploit this system impedance principle using the rear door speakers
'instead' of the tailgate, you can disconnect the tailgate speakers by pulling the harness connectors off of the speaker terminal blocks, and then add a
jumper to both the L & R tailgate speaker wires.
CAUTION! Before doing this, I had already disabled the party mode's
"Speaker selection relays", controlled by the pm button. When I did my 'party mode tweak', I did almost the same thing that Ryan did regarding the white wire (pin #1) that he cut on the back panel of the HU, but there is one more thing that I needed to do. I cut the white wire at the party mode switch.
EDIT: This wire provides a
'Ground' (when the pm button is pushed in) to the 'speaker selection relays' mentioned above, and to the HU's EQ circuit. But now we don't want this button to activate the "S.S. Relays" anymore, we only want it to activate the 'High fidelity' eq circuit in the HU, so we cut that white wire from the pm button and joined it (via small jumper) to the white wire (pin #1) on the HU.
By doing this, the pm button will still initiate the hu's eq circuit when pressed in, but will no longer have the ability to select which speakers are on. So now you can have all four rear speakers on at the same time (in series) but if you choose to, you can disconnect the tailgate speakers, add a jumper to their wiring harnesses, and really boost up the output of the backdoor speakers; as was once done w/the tailgate speakers.
NOTE: You must
NEVER jumper over speakers while wired in
parallel or you will cause damage to the HU/amplifier! This is why I disabled the pm relays first, so there would be
no chance of this happening. Hope this helps to clarify some things about this system and offers you more configuring options for your particular listening taste, chow!