I'm posting this separate from the thread for 6-speaker 2024's, as I found out a few things in my '25 3-Hatch. If anyone has found more info or can add to this, please comment below.
It's true - Mazda cheaped out and did not put rear speakers in the rear doors of the Preferred & lower trims. The non-Bose Carbon & Carbon Turbos DO have the rear door speakers (8 total speakers, non Bose) and this is important for us lower trims, based on what I found. There was conflicting info in other forums about the "6 Speaker" audio, so I did some digging and here's what I found for the 2025 Japanese built 3 Hatch Preferred (it's a different power amp than 2024).
Others have said the 6-speakers are 2 front door drivers, 2 front door tweeters, one small small sub woofer under the driver's side dash and a center "dash" speaker in the grill behind the infotainment screen. Not in my car. In the 2025 Preferred Hatch (and I'll guess lower trims with 6 speakers) there are 2 front door drivers, 2 front door tweeters and TWO small sub woofers under the dash -- one you can see on the driver's side and a second one on the passenger side under the glove box. There is a removable plastic panel under the glove box and the right sub is above it, with light blue & pink wires. Total = 6 speakers.
Since there is a fader control in the audio infotainment interface for the rear speakers I couldn't believe some pro audio posts on other sites that stated the 6 speaker amp does not have outputs for the 2 rear door speakers. One YouTube pro audio shop also stated there was only one small sub instead of two. I set about finding the part number for my amp and a wiring diagram for it. Here's what I found:
The non-Bose audio amps found under the passenger seat, seem to come from Mitsubishi. Some are made in Mexico in 3 sedans made in Mex and some from Taiwan for the Japanese 3 Hatches. I have a 5-year Mazda Gold warranty that I don't want to void, so I couldn't remove the passenger seat to pull the amp. I was able to remove the plastic amp cover (it's tight!) and get the variant # off of the amp. Mazda has used a half dozen variants of these amps in non-Bose Gen4's! The amp part # for my 2025 Preferred Hatch is ER90-66-A20A. Note: this is different than the unit in the 2024s.
I could not find a wiring diagram or schematic for the unit. I searched the part # at the official Mazda Parts Online (link below) and when I expanded the illustration, the spec sheet stated this amp is for BOTH the 6 speaker and 8 speaker Carbons! That can only mean that this amp DOES have output terminals for the rear doors. Since I didn't pull the seat, I couldn't get to the Molex plug with the speaker outputs to trace the wires.
I did see a pro audio clip on YouTube where the technician pulled off the right B-Pillar cover and was able to get to the wire harness that feeds the rear door electronics. When he pulled out the Molex plug, he saw 2 wires going in that did not feed out the other side of the plug to the door, which he figured were the rear door speaker wires everyone has been looking for -- they did not proceed to the speaker mounts in the doors. Are you kidding?
Again, not wanting to void my warranty, I didn't open my B-Pillars to check these possible wires for voltage or audio output. Being a retired studio owner / audio engineer, this is killing me! If anyone is bold enough to pull the passenger seat or open the B-Pillars to check, please report here. Here's the amp part link showing it is also for the 8 speaker non-Bose:
It's true - Mazda cheaped out and did not put rear speakers in the rear doors of the Preferred & lower trims. The non-Bose Carbon & Carbon Turbos DO have the rear door speakers (8 total speakers, non Bose) and this is important for us lower trims, based on what I found. There was conflicting info in other forums about the "6 Speaker" audio, so I did some digging and here's what I found for the 2025 Japanese built 3 Hatch Preferred (it's a different power amp than 2024).
Others have said the 6-speakers are 2 front door drivers, 2 front door tweeters, one small small sub woofer under the driver's side dash and a center "dash" speaker in the grill behind the infotainment screen. Not in my car. In the 2025 Preferred Hatch (and I'll guess lower trims with 6 speakers) there are 2 front door drivers, 2 front door tweeters and TWO small sub woofers under the dash -- one you can see on the driver's side and a second one on the passenger side under the glove box. There is a removable plastic panel under the glove box and the right sub is above it, with light blue & pink wires. Total = 6 speakers.
Since there is a fader control in the audio infotainment interface for the rear speakers I couldn't believe some pro audio posts on other sites that stated the 6 speaker amp does not have outputs for the 2 rear door speakers. One YouTube pro audio shop also stated there was only one small sub instead of two. I set about finding the part number for my amp and a wiring diagram for it. Here's what I found:
The non-Bose audio amps found under the passenger seat, seem to come from Mitsubishi. Some are made in Mexico in 3 sedans made in Mex and some from Taiwan for the Japanese 3 Hatches. I have a 5-year Mazda Gold warranty that I don't want to void, so I couldn't remove the passenger seat to pull the amp. I was able to remove the plastic amp cover (it's tight!) and get the variant # off of the amp. Mazda has used a half dozen variants of these amps in non-Bose Gen4's! The amp part # for my 2025 Preferred Hatch is ER90-66-A20A. Note: this is different than the unit in the 2024s.
I could not find a wiring diagram or schematic for the unit. I searched the part # at the official Mazda Parts Online (link below) and when I expanded the illustration, the spec sheet stated this amp is for BOTH the 6 speaker and 8 speaker Carbons! That can only mean that this amp DOES have output terminals for the rear doors. Since I didn't pull the seat, I couldn't get to the Molex plug with the speaker outputs to trace the wires.
I did see a pro audio clip on YouTube where the technician pulled off the right B-Pillar cover and was able to get to the wire harness that feeds the rear door electronics. When he pulled out the Molex plug, he saw 2 wires going in that did not feed out the other side of the plug to the door, which he figured were the rear door speaker wires everyone has been looking for -- they did not proceed to the speaker mounts in the doors. Are you kidding?
Again, not wanting to void my warranty, I didn't open my B-Pillars to check these possible wires for voltage or audio output. Being a retired studio owner / audio engineer, this is killing me! If anyone is bold enough to pull the passenger seat or open the B-Pillars to check, please report here. Here's the amp part link showing it is also for the 8 speaker non-Bose:
ER9066A20A - Amp, power-audio. Antenna, speaker, systems - Genuine Mazda Part
Genuine Mazda Part # ER9066A20A (ER90-66-A20, ER90-66-A20A, ER9066A20) - Amp, power-audio. Antenna, speaker, systems. Fits Mazda3
parts.mazdausa.com
