Goodman Furnace: Check ECM high voltage power circuits
Check ECM high voltage power circuits on a Goodman furnace: This is the test for line voltage getting to the ECM blower motor through the 5-circuit power connector. Straightforward once you know the pin pairs. You will have power on while you meter, so keep your hands clear and use the right meter range. A motor can look dead when it simply isn't being fed.
Applies to: ECM blower motors on ACVC96/AMVC96/GCVC96/GMVC96
Common causes of check ecm high voltage power circuits
- No supply voltage reaching the furnace
- A bad connection or break in the 5-circuit harness feeding the motor
How to fix check ecm high voltage power circuits: step by step
- Disconnect power, then unplug the 5-circuit power connector from the ECM motor.
- Turn power on and measure between pins 4 and 5. It should equal the furnace supply voltage.
- Measure between pins 4 and 3. It should be about zero volts.
- Measure between pins 5 and 3. It should equal the furnace supply voltage.
- If there is no voltage, check the furnace supply voltage (see section S-1).
- Disconnect power and reconnect the 5-circuit harness.
If the unit shows an error code, look it up: Goodman Furnace codes
Source: Goodman GMVC96 service and troubleshooting manual, p. 45-46. Written in our own words as a summary; always check the original manual.
General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.