View Single Post
Old 04-25-2020, 07:46 PM   #25
LimitedSlip
Senior Citizen Member
 
LimitedSlip's Avatar
 
Join Date: Jul 2018
Drives: Then-1977 Celica GT Now-2017 860SE
Location: In A Galaxy Far Far Away
Posts: 393
Thanks: 145
Thanked 385 Times in 201 Posts
Mentioned: 12 Post(s)
Tagged: 1 Thread(s)
I wasn't aware of this:

Quote:
Originally Posted by soundman98 View Post
but note that tcoat has said that bluetooth calls go only through the lower door speakers, meaning that there's some other significant changes made for the wiring as well.
But now I am:

Quote:
Originally Posted by Tcoat View Post
Since the phone works through the door speakers the best you can get is a whisper volume even cranked u to 30.
Which leads to a couple questions:
1. As Tcoat posted above, there are dealer installation instructions for the Harmon radio. What is in the dash when the 2020 models arrive at the Port of Entry? Some other HU? A hole in the dash? The Toyota web site seems to indicate that all 2020 86 models have a HU with "Clari-Fi" which is a Harmon trademark. So, no more Pioneer head units?

2. I can come up with two ways that the phone audio can work as Tcoat describes:
a. The door speakers are wired directly to their own amplifier channel in the headunit.
b. There is a low pass filter being applied to the phone audio eliminating the high frequency audio

If 2a is the case it would explain how Harmon is dealing with the "short circuit load" concern. It would also require completely different wiring of the D49 dash junction connector AND four additional conductors to the rear of the HU. The usual 6 and 10 pin speaker plugs are already fully used. The 28 pin connector has a few available locations but it usually only carries low level signals, not speaker outputs. The instructions don't indicate that there are any new connectors on the rear of the HU.

If 2b is the case, it might be some part of the "Clari-Fi" processing but reviews suggest that Clari-Fi boosts the highs, not eliminate them. And, eliminating the high frequencies from audio causes it to be muddy and unclear, the opposite of what would help clarify it.

Conclusion? Someone needs to either find a 2020 wiring diagram or take a 2020 dash apart and make a few measurements.
LimitedSlip is offline   Reply With Quote
The Following 2 Users Say Thank You to LimitedSlip For This Useful Post:
soundman98 (04-25-2020), Tcoat (04-25-2020)