genw3st

Hey all,

I have a 2018 F-150 STX with the 3.5. Just got the VML3Z18808A upgrade, plugged into the factory harness, mounted it in the back. I opened FORSCAN and changed the appropriate code in the ACM 721-01-01 to xxx8 but the sub still doesn't work. I also tried modifying ACM 721-01-02 to the "6 Speaker Crew" but no luck.

There's no way my 5Star tune would be interfering is there? Tomorrow I'm going to grab my tester and check current at the wires. I did see that XL trucks are excluded from this upgrade on the Ford website, but not sure if the STX with the Sync 3 stereo is a different story. It's worth noting that the connector was there behind the rear pillar panel, so I did have something to plug and play - the subs just not working.

Any and all help is appreciated.

genw3st

May have found the issue here - https://www.f150forum.com/f30/kicker-ford-no-power-419109/

tl;dr red wire on harness doesn't actually have power, you need to get power to that harness... or so it seems.

genw3st

Well that wasn’t it, there’s power to the amplifier - so either the Forscan changes I made aren’t working or the unit is defective. It’s a brand new one, too.

Notorious DRIVE

Any luck with this? I have a 2018 STX 5.0 and am having the same issue. Power but no sound/signal. I tried both enable sub and 7 channel audio neither worked. I thought I might have a cold solder, but now I think it might be something else. I’d prefer to use the factory connections rather than tap into the rear speakers.

MustangAndy

It's a 50/50 chance the signal coming from the factory headunit is loud enough. Had the same issue on my 8" Kicker Hideaway and have seen others with the same problem. You're gonna have to clip and tap the rear speaker wires (most likely).



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