What to check yourself
Step 1. Run the kitchen tap hot before you press Start
GE's own advice and it works. The pipe between the water heater and the dishwasher holds a length of cold water, and the machine's first fill takes exactly that. Run the tap until it is hot, then start the cycle.
Step 2. Check the water heater setting
Many are set to 110 or 115 to save energy. The dishwasher wants 120 at the machine, which means a little more at the heater. Raise it a notch and give it a day.
Above 120 the tap water can scald a child. If you raise it, tell the household.
Step 3. Do not run the shower or the washing machine at the same time
Both pull hot water away from the dishwasher. If C6 only appears in the evening when the house is busy, that is your answer, and it costs nothing.
Step 4. Pick a longer cycle or a heat option
Heavy, Pots and Pans, or the added heat option give the heater more time to raise the temperature itself. GE suggests it, and on a machine with a weak supply it is a fair workaround.
What a technician will look at
Described so you know what you are paying for, not as steps to repeat.
Test the heating element and the thermistor
If the tap is hot and the code stays, the machine is failing to add heat. The element is metered for continuity and the thermistor for a sensible resistance at room temperature. A thermistor that reads low makes the control think the water is cold when it is not.
When to call a technician
When the water at the tap is genuinely hot, the cycle is a long one, and C6 still appears. At that point the heater or its sensor is at fault, and both are under the tub.
What the repair costs
| Repair | Part only | Fitted by a technician |
|---|---|---|
| Hot water at the tap, heater setting, cycle choice | - | Free |
| Diagnosis alone | - | $70 to $130 |
| Thermistor replacement | $30 to $45 | $125 to $300 |
| Heating element replacement | $25 to $75 | $200 to $350 |
A new machine of the same class runs $500 to $1,500. Once a quote passes about a third of that on an older appliance, the repair stops making sense.
Codes people confuse this with
Questions people ask
- Is C6 a fault in the dishwasher at all?
- Usually not. It is a measurement of the water you gave it. The machine only becomes the suspect once the tap water is hot and the code persists.
- What is the difference between C6 and C7?
- C6 is a cold reading. C7 is no reading at all: the sensor circuit is open or shorted. C6 points at the water heater first; C7 points at the sensor first.
Which machines this applies to
Applies to
Older GE, GE Profile and Hotpoint dishwashers with electronic controls: GSD, GHD, PDW, EDW, GLD and HDA model prefixes.
Last checked
2026-08-28