EE5 Open fuse (short in low voltage wiring)

What the control is telling you

The low-voltage fuse on the control board is open, usually because of a short in the 24 V wiring (thermostat, outdoor unit or accessory wiring).

Applies to: Goodman/Amana/GMC gas furnaces, 9-speed ECM, 7-segment control. Two-stage 96%: AC9C96, AM9C96, GC9C96, GM9C96. Single stage 80%: VC9S80, VM9S80, AC9S80, AM9S80, GC9S80, GM9S80. Single stage 92/96%: VC9S96, VM9S96, AC9S96, AM9S96, AM9S92, GC9S96, GM9S96, GM9S92

Likely causes

• Short in thermostat, outdoor unit or accessory 24 V wiring
• Fuse failed

Test and repair steps

1. Measure R to C if the transformer secondary shows 24 VAC but R-C on the terminal board reads only about 13 VAC, the board fuse is blown.
2. Before replacing the fuse, find the short: disconnect thermostat and outdoor unit wires and check each run for a short to ground or between conductors.
3. Repair the shorted wire (often a nicked thermostat cable or a shorted contactor coil), then replace the fuse with one of the same rating.
4. Restore power and run heat and cool calls to confirm.

Settings for these units

Normal status displays (7-segment) · Goodman/Amana GM9S96/AM9S96

These are normal operating displays, not fault codes.

Normal status displays (7-segment) · Goodman/Amana GM9S80/AM9S80

These are normal operating displays, not fault codes.

• Normal status displays (7-segment) · Goodman/Amana GM9C96/AM9C96
• Minimum recommended filter size · Goodman/Amana GM9C96/AM9C96

Models that show this code

80 models in Goodman/Amana GM9S96/AM9S96, Goodman/Amana GM9S80/AM9S80, Goodman/Amana GM9C96/AM9C96

Other codes on the same units

• EE1 Pressure switch closed at start of heating cycle
• EE2 Pressure switch did not close (inducer runs, no ignition)
• EE3 High (primary) limit open
• EE4 Flame sensed with no call for heat
• EE6 Low flame signal
• EE8 High-stage pressure switch closed at start of heating cycle
• EE9 High-stage pressure switch did not close
• EEA Reversed line polarity or grounding error