[ryan stewart]

This is for pulling the Logic 7 amp out of the trunk, opening it up, and then replacing the fans that have either died or are whining really badly when running

Time: I did it in 37 minutes, but I used to solder electronics professionally. Honestly it shouldnt take more than an hour and maybe 2 beers for any decent mechanic.

Parts/tools (needed):
8mm socket
T10 torx bit
T9 torx bit
Two picks or two small flatheaded screwdrivers
Soldering kit
Heat shrink tubing

Two Sunon MF30151V1-1000U-G99 fans (you may also be able to get the original Sunon GM1203PHV1-8A off ebay, but from China and lord knows how old it is)

I got my fans from Mouser Electronics in Texas: https://www.mouser.com/ProductDetail...WUtyEhZw%3D%3D

They had plenty in stock and got them to my door in 48 hours.

Parts/tools (Optional):
Eye Protection
Some thermal compound for CPUs
Dielectric grease
Helping hands (for soldering)

First step is lifting up the primary trunk panel exposing the tool kit. This may vary based on car. Then remove the drivers side rear side panel next to the tool kit. In my case (E91) its just a latch and it comes loose as a compartment.

To remove the tool kit there are two 8mm screws, one on the side of the car and one on the rear, the tool kit will then lever out from the plastic bracing of the under trunk paneling.

Youll be faced with the amp in a metal bracket:


First you will want to unplug the optical connection, its a simple pinch and pull plug pinching the top and bottom. Then you will need to pull the electrical connection. This one is one of those slide to release connectors and its very tight. Grab the ribbed portion and pull towards the center of the car, one you get a little space might need to a screwdriver to lever it the rest of the way. You can see the ramps on it that disengage the plug as you pull that direction.

Now there are two ways to actually remove the amp.
1. Those two red circles at the bottom are showing tabs to two metal strips. The amp has loops in it that hang down through slots in the bracket and those strips slide through them to lock it in, just pull them to the middle of the car.
2. You can undo 4 8mm screws and remove the entire bracket. Id only do that if the strips are too tight.

Move the amp to a workbench (preferably one with a beer on it and surrounded by Italian motorcycles)

On the business end of the amp there are two screws, unscrew them with a T10 Torx bit:


Then on the other end there is one more T10 Torx screw:


Now turn the amp on its side, for this next bit you will need the two picks or flathead screwdrivers. You will find metal clips running alone the base on each side of the amp.

You will need to lever under them with the two screwdrivers to pop them straight out, they are just springs. This is where the eye protection might be handy just in case they go flying on you:


There are 3 on one side and 4 on another, remember which side for reassembly.

Once they are off you will then need to carefully (but somewhat forcefully) unclip the heat sink. There is a lip on the lower portion of the body (down by the clips) that runs the full length of the amp on each side, pictured below:


I carefully levered a flathead under the lip to pull it outward until it popped loose. Then do the other side.

Once you do that the heat sink should lift straight off exposing the creamy goodness:


Make sure and keep the underside of the heat sink safe and clean, it has your heat sink surface and some thermal compound you dont want to wipe off if you are not replacing it:


Ok back towards the business end there are two T9 Torx screws holding the fan assembly in. The fans are plugged in with two 3 pin headers, just yoink on the wires, they are not in tight:


Once you get the fan assembly out also move the amp to a safe place, dont want to go poking at exposed electronics or wiping any more of that thermal compound off.

The fans, at this point, are just held in with springs built into the housing, just stick a small flathead screwdriver into the slot and push, they will pop loose:


Once they are loose you can just pop that grommet, its not captive and its a split grommet so the wires will come out the side of it.

Here is old and new, side by side:


Now I am just going to cut and solder. If you wanted to get fancy you could source some 3 pin header kits and build them from scratch, Id rather solder.

Now I should really stress at this point some tweezers and helping hands would make this a LOT easier, these are some tiny wires.

First things first, dont forget to put your heat shrink on the fan side of the wires, its really hard to do that AFTER you solder. Then just cut and strip where you wanna cut and strip. I left a ton of wire for a do over, but you can just tuck it in the housing:


Solder those bad boys in place. Id recommend (but its not required) putting a little dab of dielectric grease on your solder joint before locking down that heat shrink. The act of compression will push air out leaving that grease in any gaps and helping waterproof that joint. Its probably fine, Im just OCD about my soldering.

Button it up and move onto the next fan:


Once you get both fans wired up its just reverse the removal. I would note that my fans were blowing out instead of sucking in but honestly as long as they are both pointing the same way I doubt it matters, its not the best design either way.

When you get to the point of placing the heat sink back on the circuit board make sure and note the correct direction. One side has those MOSFETS beyond the 6 symmetrical integrated circuits. You need to go the right way for the chassis screws to line up but if to look at the chips and grease its pretty obvious.

Now would be the time to replace that grease if you have some, if you dont just use a blade to move some of that excess from the sides back into the middle, mine had PLENTY to reuse if I had gone that route.

Screw it all back in, slap that bad boy in its bracket, plug both plugs in, button it all up, and enjoy only being able to hear the fans running at full blast if you put your ear to the floor of your trunk.

[ryan stewart]

I was too lazy to get a before but here is an after. Remember this is with the amp completely exposed. What you are hearing is the whoosh of air from fans moving 9500rpm from a foot away with nothing in between. I would have gotten one after buttoning it up but my phone wouldn't register the sound its that quiet:

https://photos.app.goo.gl/s7R6jYfjbwkajJ9H6