Fan fault codes 
P0686, P0687, P0691, P0692, P0693, P0694, P0695

Check  off the following diagnosing boxes:
- Do a tech2 read out

- Faults occur after a quick pull above 3500 rpm
- Faults occur when the engine is hot

If you have several fan code faults active follow the following procedure to verify fan relay is still functional:
- Go to fan settings in the tech2 activate the 0, 1, 2, 3, 4 setting to see if all are manually activateable.
- Check UEC for blown fuse for fan relay or ECU relay.

- Fault occurs after a reset (battery clamp removal) when the engine is hot or after a pull above 3500 rpm.

Solution: 
Your ECU is broken you can solve this here

If one of the above does not apply follow the following procedure
Grab the tech 2, go through fan settings in the tech2 activate the 0, 1, 2, 3, 4 setting to see if all are manually activateable. Sometimes it may take a few attempts for it to go into the fault.
You can also measure with a test light if a tech 2 is not available.

See if your engine fan itself spins freely, if not lubricate it a little, this can solve issues temporarily
See if your airco pump is still functional - usually only an issue if only P0695 is active.
See if your airco pump has enough R134A gas available - this can trigger P0693 P0694 or P0695.

Solution for these issues is to go to a garage and let them fill up the airco, replace the pump, replace the fan relay.

If P0686 or P0687 is your only fault code do the following:
Check in the UEC if your ECU relay is still good. Also check the relays infront of the battery.
Check the ground points below your battery, on your gearbox, and in the case of an automatic check the bracket attached to the ground strap.
Also verify the automatic gear box ground strap is still whole.

If all of this is good:
Your ECU is broken you can solve this here