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Error code reference
Denso Air Conditioner Error Code E20
DC voltage abnormality: DC voltage or current at or below, or at or above the specified value detected.
SourceDENSO CM 25 Air Conditioner - Full Service Manualp. 45, 54
Diagnostic procedure
The full E20 procedure
Step 1 is visible so you can confirm you are on the right page. The remaining steps, the ones that tell you whether to actually replace a part, unlock with any pass.
MyPros+ · DiagnosticsStep 1 preview
1
First diagnostic step
Check if the supplied voltage to the unit is unstable due to external influence, then RESET the controller. If error persists, replace the relay board and initialize the fan motor.
SourceDENSO CM 25 Air Conditioner - Full Service Manualp. 45, 54
More steps, wiring diagram references, and verified part numbers
Includes expected resistance and voltage values, connector pinouts, and supersession notes for replacement parts.
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Where this code is documented
1 manual in the MyPros+ library documents this code for Denso air conditioner.
Models covered by the manuals that document this code
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