Sinclair SCV-1400EB, Service Manual

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6.4 L20: Module overheat protection
Description

IPM module temperature exceeds 105 °C.

After the fault, the compressor stops running, and if the fault disappears after one minute, the compressor starts again.
Trigger/resume condition
 Trigger condition: IPM module temperature exceeds 105 °C;

Resume condition: The compressor shuts down after a fault, and resumes after reaching the fault exit condition (The
module temperature is lower than 105 °C) one minute later;

Reset method: Automatic recovery after reaching the fault exit condition one minute later.
Possible causes
 IPM fixing screws are not tightened, resulting in poor heat dissipation;

The heat dissipation silicone of the IPM module is not evenly spread, resulting in poor heat dissipation;

The system lacks refrigerant or the refrigerant radiator pipeline is blocked, resulting in poor heat dissipation of the
refrigerant radiator;

The system refrigerant radiator is abnormally welded, resulting in too large thermal resistance and poor heat dissipation;
 The module board IPM temperature detection circuit is abnormal.
Procedure
L20
IPM fixing screws are not tightened
Yes
Tighten IPM fixing screws
NO
The heat dissipation silicone is not applied or the
heat dissipation silicone is uneven
Yes
Reapply dissipation silicone
NO
The system lacks refrigerant (Use discharge
temperature and pressure to judge)
Yes
Refill refrigerant
NO
Refrigerant radiator clogged
Yes
Clean the pipe
NO
Drive board fault
Yes
Change the drive board