Brand: GE Model Number: GDT580 Main Symptom: “Normal Cyle” runs 2 hrs instead of 75 minutes that it used to What happens & when: Takes longer when used
Error Code (if any):
Parts or tests already tried: Filter is cleaned regularly. I thought maybe heating element wasn’t working. I ran sanitize cycle and it completes with no errors and “sanitized” light is illuminated when complete. According to the manual, if the heater element wasn’t working, this light would not be illuminated.
Photos / video link:
Other observations: The dishwasher still cleans great. It is well maintained. Filter cleaned multiple times per week. The incoming water is softened water. Only powder detergent is used and reduced levels due to soft water. No rinse aid is used.
Noticed that toward the end of “normal cycle” there area few times where it just fills and then drains immediately without any washing. Then it will fill, do a final rinse and complete the cycle. I’m not sure what the standard sequence of operations is for “normal cycle”. I asume it is pre-wash, wash with soap, and rinse but maybe there is more?
Since the dishwasher is still cleaning well and the Sanitized light comes on at the end of the cycle, I agree that the heating element is likely working correctly. On GE dishwashers, the sanitize cycle verifies the water reached the required temperature. If the heater had failed, the cycle would typically end with an error or the Sanitized indicator would not illuminate.
A few things are worth checking:
Verify the cycle options haven’t changed. Some GE models have an “AutoSense,” “Boost,” “Steam,” or “Dry Boost” option that can significantly increase the cycle time. Also make sure the dishwasher isn’t defaulting to a different version of the Normal cycle.
Check the incoming hot water temperature. Even with a working heater, if the water entering the dishwasher is below about 120°F, the control will extend portions of the cycle while it heats the water. Run the kitchen faucet until it’s fully hot before starting a cycle, then measure the water temperature with a thermometer if possible.
Test the turbidity (soil) sensor. The Normal cycle on GE dishwashers is adaptive. It uses a soil sensor to determine how dirty the water is and adjusts the cycle length accordingly. If the sensor is dirty or beginning to fail, the control may think the dishes are dirtier than they really are and extend the cycle. The sensor can often be cleaned, and on many models it can also be tested in diagnostic mode.
Check for stored error codes. Even if there are no obvious symptoms, the control may have logged a fault that points toward a sensor or control issue.
Regarding the sequence you noticed where it fills and then immediately drains without washing—that can actually be normal. GE dishwashers often perform short fill-and-drain or purge operations during adaptive cycles to sample the water, clear residue, or prepare for the final rinse. By itself, that isn’t necessarily an indication of a problem.
I’d recommend starting with these questions:
Has the cycle gradually become longer over time, or did it suddenly change?
About how long is it taking now—2 hours, 2½ hours, or even longer?
Could you provide the complete model number? (GDT580 is only the series. It will look something like GDT580SSF8SS or GDT580SMF7ES.)
With the full model number, I can also provide the exact procedure to enter the dishwasher’s diagnostic mode and check for stored error codes, along with the proper tests for the turbidity sensor and temperature sensor.
Normal cycle used to take about 75 minutes. The display still says 75 minutes when you select Normal before hitting start. Now it takes about 2 hrs or just under.
I didn’t notice until recently. If I had to guess, I would say it has been a gradual increase but I cannot say that with any certainty.
Ok I’m going to attach a copy of the tech sheet for reference, but the procedure is When the dishwasher is in Standby Mode (Cycle Selection Mode), press and hold the Cycle Select and Start pads simultaneously for 5 seconds. If LCD is present, the LCD should remain off
OK so you have a fault for a bad thermistor that would definitely make it run longer since it is having trouble detecting the temperature of he water in the dishwasher. on yours the thermistor is integrated into the flood switch assembly ( GE WD21X10519 Dishwasher Flood Switch Assembly | Genuine OEM Part )
Location
The flood switch and thermistor are located inside the tub at the very bottom, beneath the filters. You can access it directly from the inside of the dishwasher by removing the dish racks and the filter assembly.
How to Access and Replace
Remove Filters: Take out the lower spray arm, the fine filter, and the coarse filter inside the tub.
Access the Sensor: Locate the mounting bracket at the bottom of the sump area, held by two 1/4-inch hex head screws.
Remove the Part: Carefully soak up any water in the sump to prevent spills. Remove the retaining screws, lift the assembly, and disconnect the wiring harness beneath it.
Install the New Part: Moisten the O-ring on the new part, reconnect the wiring harness, and secure it back in place. [1]
I actually have a spare one of these on hand! Yay. I replaced it a long time back when I was using too much detergent and didnt know it and switching out this part didn’t fix it (obviously) so I kept it.
I will report back if it works. Thank you so much!
Last run was about 100 minutes. Less than 2hrs+ like previous, but still longer than 75. I dont think “Normal” is supposed to be using the wash sensing. I think the wash sensing is only used when “Autosense” cycle is used. Normal is supposed to be a set time cycle based on what I see in the OM. If it does use sensing, maybe this is normal but I rinse before loading the dishwasher so I think there should be minimal extra washing needed.
When checking for codes again after replacing the float switch/thermistor, the “boost” light is no longer on and that one indicated the thermistor. So that is good.
Code display still has the “autosense” light on and the “lock controls” light on. It doesn’t seem there is an error associated with these, correct?
I take it back on the Normal cycle. I just found a small blurb saying Normal can go from 1hr15min to 1hr50 minutes. I guess I am back within the normal range.
When the AutoSense indicator light on your GE dishwasher is active, it means the machine is either running that specific cycle or the turbidity (soil) sensor is currently measuring the water’s cloudiness to adjust cycle length. If the light is flashing unexpectedly, it usually indicates a paused cycle or a sensor fault
Thank you. I wasn’t 100% sure because when I unplug the dishwasher for 30sec, plug it back in and then go to the error display mode, only the lock controls light is illuminted. But then after I run a wash cycle and go to the error display mode, then the autosense light is on. Thanks for confirming.