E1/El 01 (Indoor And Outdoor Unit Communication Error Diagnosis And Solution) - Pioneer QUANTUM INVERTER Series Service & Troubleshooting Manual

7.2

E1/EL 01 (Indoor and outdoor unit communication error diagnosis and solution)

Description: Indoor unit cannot communicate with outdoor unit.
Recommended parts to prepare:
• Indoor PCB
• Outdoor PCB
• Short-circuited component
Troubleshooting and repair:
Power off, then restart the unit after
Does the error code
Check the wiring connection
between indoor and outdoor
unit , are they good?
Measure the DC voltage between N
and S (Black pin to S , Red pin to N
For units with both main PCB and IPM board
Check the AC voltage of L, N
output to IPM board, is it same
components connected to main
PCB such as 4 way valve , heater ,
AC fan one by one to check their
resistance. Is there any component
Unplug electronic expansion valve.
Check if the DC 5V , 12 V to main
Note: For certain models, outdoor PCB cannot be removed separately. In this case, the outdoor electric
control box should be replaced as a whole.
2 minutes.
No
disappear ?
Yes
Correct the connection or
No
Yes
L2
/ The value is fixed and close
/ L2 ).
The value is always positive
For units without W
wire
Check the wiring connection
No
as power input ?
Yes
Unplug all the high voltage
Yes
short circuit ?
No
Check the DC 5V , 12 V
from IPM board to main
PCB, are they normal ?
No
Yes
PCB are OK
No
Replace IPM board
Troubleshooting

Solved
change wires
The value is alternative
from negative to positive
to 0
For units
with W wire
from outdoor terminal to
outdoor PCB and wiring
between PCBs if there is
more than 1 PCB
For units with only one PCB
Replace main PCB Replace outdoor PCB
Replace short-circuited
component and main
PCB
Yes
Replace short-circuited
component and outdoor
PCB
Replace coil of electronic
expansion valve
20
Check the wiring connection
from indoor terminal to indoor Replace indoor PCB
PCB, are they good ?
Turn on the unit, check if W
and 1 (L) is connected ?
Yes
Check if the power LED is
Yes
on ?
No
Unplug all the high voltage
components connected to main
PCB such as 4 way valve, heater,
Yes
AC fan one by one to check their
resistance. Is there any component
with a short circuit ?
No
No
Unplug electronic expansion valve.
Yes
Check if power LED is on?
No