If the sampling voltage is lower than 0.06V or higher 
than 4.94V, the LED displays the failure.
Sensor Error F1 / F2 / F3 (page 1 of 4)
Troubleshooting:
Error may only display every 3 minutes, during this time you may 
see either “normal display” or “88” on indoor unit or wired control.
If after parts 
replacement, error is 
still displayed, contact 
your local CE Technical 
Support Rep.
Check the connection between
the temperature sensor and the PCB. 
No
Measure the sensor’s resistance value.      
Charts on next 3 pages.
Yes
Is it properly wired?
Is it a close 
match to the 
chart?
No
Reseat/Reconnect 
Sensor connections
and retest system
Yes
Replace PCB Sensor 
is connected to
Error to Sensor Location
F1 (E53) – T4 Outdoor Ambient Temp
F2 (E52) – T3 Condenser Temp ODU
F3 (E54) – TP (T5) Comp. Discharge Temp 
Replace sensor
38MAQB18~48K, 38MAQB09~36R—3, 38MARBQ09~36AA3 Outdoor Units
Follow the “1st Steps for DLS Troubleshooting” 
in the beginning of this guide, if you have an 
active error, procedure below. 
Continued on next page