TheBruce

For all you 997 owners who have the optional Bose stereo and think the sound quality sucks, there may be an simple reason: its just not working!

There are a lot posts complaining about the 997 Bose stereo. There are two primary issues most people face:

1. It has a tinny sound quality with not much bass
2. The Bose “Autopilot” feature, which is supposed to automatically adjust the volume based on speed + cabin noise, doesn’t actually work.

I have both these issues. The funny thing is when I first test drove the car I remember the stereo sounding much better and having a lot more bass. However since I have owned the car the sound quality has been underwhelming and I’ve been getting carpel tunnel turning the volume up/down at every stoplight.

It wasn’t terrible enough for me to think something was wrong, I just figured the Bose system was a piece of crap.

After piecing together a number of posts on the topic I found the simple fix: just pull the fuses for the PCM and Bose amp (the D9 PCM and D10 Bose fuses pictured below) to reset the amp and voila.

I pulled the fuses while the key was still in the ignition and power was running to the PCM. I then turned the ignition off, put the fuses back in, and restarted the car. As soon as I did that the sound quality improved dramatically and the bass was vibrating my car seat.





What I suspect happened is the Bose amp has not been working since my battery died (my Indy left the key in the ignition over the weekend). After they jumped it they had to reset a bunch of CEL codes and I think it frazzled the Bose amp. So i’ve been driving around for 6 months without the Bose system working and didnt even realize it.

I havent been able to get on the highway to confirm its also solved issue #2 with the Autopilot feature, but will keep you posted once I do.

motopix

Interesting. When my PCM was dying, I pulled D9 many times during diagnostics. I finally ended up replacing the PCM and the new one (labeled '08 vs. my '06) sounded much better. I put it down to updated hardware. Maybe it was the fuse pulling.

I don't think my autopilot works though. So I'll try pulling them both and report back.

TheBruce

The Bose amp is fuse d10.

Frank996

How does one know if one have the Bose system or not (I mean the the "bose" labels will give it away of course, but are also easily removed - at least they were on my old 996 4S)?

Petza914

There's a subwoofer above the rear seats with ports on both sides. That's probably the easiest non "Bose tag on the door speakers" way to know.

TheBruce

I took the car out on the highway yesterday to test the Autopilot after the reset. I "think" its better but it might be a placebo effect.

Frank996

Thanks Petza914...

I think it may not have the Bose system as the sound is very "flat" but it does get louder when I speed up (tire noise etc increasing).

Sorry for going off topic.

stronbl

I've noticed the same behavior with my audiopilot. It works but not very dramatic in up and down volume.

BER

Bruce.

On my 2012 997.2 C2S, fuse E4 (30 Amp) is the Bose Amp. E9 was the PCM.

I pulled them per your instructions. Seems better, but the "autopilot" does not appear to be doing it's job.

Thanks for posting your fix.

orange260z

I'm not an audio engineer, but I know that a lot of car stereo professionals tell you that one of the biggest improvements you can make on Bose and Harmon/Kardon systems, as well as others, is turning off the speed-dependent volume. Apparently those systems add a lot of distortion.

Astur

It might just be that my English comprehension is lacking and although I do understand what "pulling" a fuse is but are you guys saying is to remove the fuse with the radio on and put it back in or just remove it permanently?

BER

Aster,

You need to replace the fuses, then restart the car.

BER

Thanks for the tip. I turned off the Bose Autopilot and have a noticeable improvement in the sound quality. Crisper tones, more dynamic bass, etc.

Cheers.

TheBruce

Nice tip. I will try it since I still can't confirm mine works anyway :-)

Ps - i also had my Indy increase the GAL setting to 7 from the default 4 with their piwis. That didn't do anything. I suspect that setting is linked to the standard stereo and has no impact on the Bose system.

ALEV8

I removed mine- yuge improvement.