Bosch ODU Split 6 - Error Code 21 Diagnosis and Countermeasure Flow Chart

2.3.1 Error diagnosis and countermeasure flow chart
ODU Split 4, 6 and 8
Fig. 2 ODU Split 4, 6, 8
1. Wait until PCB (Inverter) DC voltage is discharged after main
power is shut off.
2. Pull out V, W, U COMP connector.
3. Set multi tester to resistance mode.
4. If the value between P and N terminal of IPM is short (0) or open
(hundreds M), PCB (Inverter) needs to be replaced, IPM is
damaged.
5. Set the multi tester to diode mode.
6. In case measured value is different from the table, PCB (Inverter)
needs to be replaced. PCB (Inverter) is damaged.
Fig. 3 PFC_IPM check
ODU Split 11s, 13s, 15s
Is installation condition normal? No -> 1. Check pipe clogging / distortion
2. Check covering (unit)
3. Check EEV connector assembly condition / normal
operation
4. Check refrigerant pressure
-> Reassemble or manage if abnormality found
Yes
Are the resistance between each phase
and insulation resistance of inverter
compressor normal?
No ->
1. Check resistance between each terminal of compressor
2. Check insulation resistance between compressor terminal
and pipe
-> Replace compressor if abnormality is found
Yes
Is compressor wire connection
condition normal?
No -> 1. Check inverter PCB assembly 1 U,V,W connector
cennection condition
2. Check wire disconnection and wiring
3. Check compressor terminal connection condition (bad
contact)
-> Reassemble if abnormality is found
Yes
Is inverter PCB assembly 1 normal? No -> 1. Check inverter PCB assembly 1 IPM normality
-> Replace inverter PCB assembly 1
Yes
Recheck power and installation
condition
Table 6 Error diagnosis and countermeasure chart
SPM3
27 26 25 24 23 22 21
P W V U Nw Nv Nu
6 720 817 722-02.1I
27 26 25 24 23 22 21
P W V U Nw Nv Nu
0.4 ~ 0.6 V
P W V U Nw Nv Nu
27 26 25 24 23 22 21
0.4 ~ 0.6 V
PFC_IPM check
U, V, W ‘ R S T
6 720 817 722-03.1I