DSP Module replacement options - audio drop out/frozen volume dail

[jensschnebele]

After much diagnostics i suspect my B&O DSP amplifier module is bad. (original part: LJ8T-18T806-AN)
they show up on ebay a lot (some quit $$$ up to 850,-), but i don't really want to put the same design back since its prone to fail. Don't want to install big aftermarket system neither. just a daily driver. (21MME AWD premium 65kmls).
seems a possible replacement could be: LJ8Z-18B849-B = Amplifier Kit those seem to be to be ~400,- at Ford dealer websites
i know it needs ForScan to program it, anyone updated the factory DSP with a 'direct but new' replacement.
what do i need to look out for?

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[rugedraw]

The files for the DSP are the same on these cars. In this case, I can get you the bootloader and files very easily to program it. You will need FORScan beta and it will literally take under 5 minutes to flash the files and configure it. Just lmk if you decide to DIY it and I can get you the files and walk you through it.

 

[jensschnebele]

Just lmk if you decide to DIY it and I can get you the files and walk you through it.

just got OBDlink EX and ForScan connected Code: DSP U3003:16-0A (Circuit Voltage Below Threshold).
reading the live VPWR_DSP (Module supply voltage) = 6.7V (when car powered up ~7.9-8.0V) that seems like a very odd voltage to report?
reading the BMS voltage its above 13... that seems to make sense
- anything else to check prior to ordering a new module ( LJ8Z-18B849-B = Amplifier Kit)
And Yes i like advise, files, guidance to do the swap as DIY project. (i have ForScan 2.3.70 release with extended license.)

 

[rugedraw]

Yea, I'm pretty sure I've seen that same code on dead DSPs before. If the voltage is regular at the BCM and low at the DSP then something got fried in it most likely. Give me until tomorrow to confirm before you order it.

You'll need FORScan beta...... not the regular version. I don't think I have a tutorial made for the DSP, but I'll plug into my truck and take some screenshots of the process for you and start sourcing the files.

 

[jensschnebele]

Update with more physical hard diagnostic.
(what a hassle to get the trim off to access the module)
i checked the harness pins 1& 2 for the DSP audio module with multimeter in right hand trunk. both show 13.5V to ground. (car powered up in accessory mode). quite convinced my module is bad. :-(

would be cool to know the reading on a known good part for: VPWR_DSP (Module supply voltage) ?

 

[rugedraw]

Update with more physical hard diagnostic.
(what a hassle to get the trim off to access the module)
i checked the harness pins 1& 2 for the DSP audio module with multimeter in right hand trunk. both show 13.5V to ground. (car powered up in accessory mode). quite convinced my module is bad. :-(

would be cool to know the reading on a known good part for: VPWR_DSP (Module supply voltage) ?

If that's the case, I would just go ahead and order the DSP. I will have the files by the time it arrives.

 

[jensschnebele]

i ordered a new module
LJ8Z-18B849-B Amplifier $363.13
from nearby Ford Dealer, but seems it might be on backorder. (had some bad experience with national distributors recently) will call the shop monday about timing.

 

[rugedraw]

i ordered a new module
LJ8Z-18B849-B Amplifier $363.13
from nearby Ford Dealer, but seems it might be on backorder. (had some bad experience with national distributors recently) will call the shop monday about timing.

Not a bad price at all for a new one. Truth is, the DSP should work when you plug it in. The purpose of programming it is just to ensure it is on the latest software. This module is not one of importance when it comes to the overall integrity of the modeule network, but if you're gonna do it, might as well do it right.

 

[rugedraw]

@jensschnebele Message me the VIN when you can. I got the files thanks to the help of another member of this forum, but want to confirm they are the correct ones for you car.

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