FIXED- no am/fm and no volume control

[Nick_rp]

See below

 

[Nick_rp]

See below

 

[Nick_rp]

Ive edited this thread to an impromptu write up (my first one, be gentle). i know this to be a common issue that goes unresolved as ive searched this forum high and low for this problem.
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The issues:
first i lost am/fm, everything else worked (BT, CD, AUX). Once in a while it would randomly come back and scare the hell out of me. Maybe 6 months later i lost the ability to adjust the volume.

The fix:
remove the radio, open the casing and your looking for the chip TEF700HN, seen circled below. Official chip description is "Digital low-IF car radio front-end"



What your looking for is spoiled solder, it will be discolored, warped or cracked.


To fix it, you need to reheat the solder either with an iron or heat gun. If you dont have steady hands like me, than an iron will be difficult as the terminals are extremely small and close together.

To fix it with a heat gun, set it to high let it heat up all the way, use a screwdriver to apply downward pressure on the chip. than apply heat to it for about 4-5 secs than remove the heat and keep downward pressure for a few secs to assure the solder has completely solidified.

And thats all, simple as that.

Some notes:

1. The melting point for PCB solder is 360-370f. The object here is to get it hot enough to basically reseat itself but not so hot that the solder melts and runs.

2. The problem with this method is its difficult to know if you were successful until you plugged it back in because as stated above, you want to get it soft but not melt and since it dosnt melt it will often still look the same as when you started

3. Using a standard size heat gun, you run the risk of unseating other components as the output cone is so large that its impossible to direct it on just the chip. Here is a link to a gun with various size cones. that is designed for pcb work.
Rework heat gun

4. The above procedure is for the regular joe with basic tools. The "proper" fix for this is a whole other animal as you have to remove the chip, clean the terminal seats with isopropyl alcohol and install a new chip. Amazon sells the chip for around $20. Tools needed are solder wick, preferably a temp controlled iron as they maintain heat better and flux in pen style. Links below for tools.

Most top rated and affordable temp controlled iron

Basic solder wick

Pen style flux

Thats all folks, i hope this helps

 

[Nick_rp]

Another tip: my eyesight isnt great so i used my phones camera to magnify the PCB to locate the problem area

 

[British Bulldog]

Now that’s how to share a ‘fix’
Hope it doesn’t happen to me but if it does………