Floatsmyboat
New Member
- Joined
- Mar 14, 2026
- Threads
- 1
- Messages
- 3
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- Location
- Houston, TX
- Vehicle(s)
- 2025 Mustang EB Premium
- Thread starter
- #1
Hello everyone!
I have had my 2025 EB for a few months now. Within a week of owning the car, I was already tearing into it for sound system upgrades. Since then, I have installed a full integrated system using the PAC AP4 FD-31 amp replacement device, Focal PS165 FE front components, Audiocontrol A1100.5, JL Audio TWK88, and a JL W3 subwoofer in the rear seat.
Big boy words aide, I am having trouble with the welcome chime reverting to the horrid early 2000's chime. I knew that this meant the ACM was having problems somewhere along the line, and was reverting to the IPC speaker. I have made a lot of Forscan and FDRS changes (Amber DRL, Adding paddle shifters, Mycolor ambient lighting install, speed limit recognition, the works) so naturally I started in software. The ACM was reporting open circuits on the Center Dash, Left/Right Tweeter speakers. I checked my wiring and realized this was caused by the T harness supplied by PAC audio, as it removes the direct connection from the ACM to the speakers. Long story short I simply disabled the speakers in Forscan by telling the car it didn't have any speakers on those pins.
But alas.. the problem remained.
It was after 6 hours of restless troubleshooting that I ran an FDRS network test and realized the DSP module wasn't responding. DUH!
As it turns out, the A2B amp replacement removed the DSP built into the amp. Now I am almost 100% certain that the ACM is unable to talk with the DSP and reverting to the fallback chime. No worries, I'll just tell the car it doesn't have a DSP (727-01-01 xxxx xxx* xx--). Well turns out if I do that, there is no audio output at all.
So now I turn to the people of the interwebs. I saw @RedRocket and his write up about using an iDatalink Maestro. I would like to ask if anyone else who did an amp replacement has had this issue? I read that the PAC device is supposed to take place of the DSP/amp and trick the car into believing whatever it says.
Just a small problem but it makes the car feel a lot cheaper and destroys the experience. Thanks!
I have had my 2025 EB for a few months now. Within a week of owning the car, I was already tearing into it for sound system upgrades. Since then, I have installed a full integrated system using the PAC AP4 FD-31 amp replacement device, Focal PS165 FE front components, Audiocontrol A1100.5, JL Audio TWK88, and a JL W3 subwoofer in the rear seat.
Big boy words aide, I am having trouble with the welcome chime reverting to the horrid early 2000's chime. I knew that this meant the ACM was having problems somewhere along the line, and was reverting to the IPC speaker. I have made a lot of Forscan and FDRS changes (Amber DRL, Adding paddle shifters, Mycolor ambient lighting install, speed limit recognition, the works) so naturally I started in software. The ACM was reporting open circuits on the Center Dash, Left/Right Tweeter speakers. I checked my wiring and realized this was caused by the T harness supplied by PAC audio, as it removes the direct connection from the ACM to the speakers. Long story short I simply disabled the speakers in Forscan by telling the car it didn't have any speakers on those pins.
But alas.. the problem remained.
It was after 6 hours of restless troubleshooting that I ran an FDRS network test and realized the DSP module wasn't responding. DUH!
As it turns out, the A2B amp replacement removed the DSP built into the amp. Now I am almost 100% certain that the ACM is unable to talk with the DSP and reverting to the fallback chime. No worries, I'll just tell the car it doesn't have a DSP (727-01-01 xxxx xxx* xx--). Well turns out if I do that, there is no audio output at all.
So now I turn to the people of the interwebs. I saw @RedRocket and his write up about using an iDatalink Maestro. I would like to ask if anyone else who did an amp replacement has had this issue? I read that the PAC device is supposed to take place of the DSP/amp and trick the car into believing whatever it says.
Just a small problem but it makes the car feel a lot cheaper and destroys the experience. Thanks!
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