If I have a Mitsubishi MR SLIM WITH 2 motor fans outdoor unit is not star

I just checked the service manual and it is;
5 blinks - Outdoor power system

The outdoor fan is supposed to be on almost all the time if the indoor unit is on. It is designed to do this due to energy consumption is from the start of motors. These fans use nearly no electric about as much as a light bulb. If your unit is cooling and no problems have occurred then its probably doing what is supposed to

P8-Abnormality in outdoor unit.

Solution:
1) Check the indoor/outdoor connecting wire in proper point.
2) Change the connection of electric wiring, if reversed phase.
3) Check the protection device, if malfunction, replace it.
4) Measure the resistance of the outdoor coil thermistor.
If the resistance is normal, replace the
outdoor controller board
Thanks.

P8-Abnormality in outdoor unit.
1) Wrong wiring of indoor/outdoor
connecting wire
2) Reversed phase
3) Protection device is working
4) Damaged outdoor coil thermistor

Solution:

1) Check the indoor/outdoor connecting wire.
2) Change the connection of electric wiring.
3) Check the protection device.
4) Measure the resistance of the outdoor coil thermistor.
If the resistance is normal, replace the
outdoor controller board.

Hope,it's helpful.

Please check your indoor motor's mechanism is faulty. Or capacitor(condenser) of fan motor is weak. Replace it.

You need a professional here. Once this has been repaired, I would suggest running the wiring to the outdoor unit inside some sort of piping to protect it.

Without seeing the unit,

1 - the condenser fan (which is in the outdoor unit) could be blown. This would cause the unit to go off on high head pressure.

2 - it could be low on refrigerant, which makes it do nothing but blow room temperature air around. The unit would go off on low pressure

3 - the filter is dirty, blocking the cooling

4 - the compressor could be shorted, or a corroded wire somewhere that feeds the contactor

Mr. Slim Ductless Splits are the best on the market and should only be repaired by a trained technician.

Hope this helps.

Check the capacitor. Rating must be within 90% of rated microfarads. If it is a dual capacitor test between C and FAN. Set your meter to read microfarads (uF).

See this document for P8 code on Mitsubishi Mr Slim MXZ30TN... It is likely you can get the fix just from following the diagnosis steps 1-7. http://www.digelair.net/pdfs/TECHLIT/MITSUBISHI/MrSlim_P-SERIES_Troubleshooting_TIPS.pdf

it is quite posible the unit is short of gas. this could make part of the indoor coil colder than the rest.