Cooling fan runs all the time on a JJW9530DDS

Cooling fan?
Surely the fan of a fan oven is there to circulate the heat within the oven to eliminate "cold" spots and shorten cooking times. Some ovens will allow the fan to switched off.

yes it would the fan continues till safe cool temperature is reached

Probably the cooling fan. There is a cabinet thermostat on most ovens these days (Especially wall or underbench models) to keep the cooling fan running after the cooking has finished and oven turned off. This fan will run for a few minutes to cool down the outside of the oven so it doesn't burn / discolour the surrounding cabinet or workbench. If the fan stays on all the time, I would say that the thermostat has probably jammed in the run or on position.

Are you sure it's the oven still running and not the built in cooling fan...next time look at the fan at the rear of the oven if it's not turning it's off and you will be hearing the cooling fan

Without knowing the make and model, this is a guess, the fans usually run for some time after switch off, to allow cooling I am guessing this carries on until you isolate the mains. If so you have a thermostat problem. It would be easier to de-fine if there were more information.

Regards
John

no/low cooling fan rotation (No RPM) single cavity or upper oven - check connection at cooling fan if ok, replace blower - DO NOT REPLACE CONTROL

Your oven has a fan to draw in cool air at the bottom of the front panel, pass it around the case, and then blow it out at a position towards the top of the oven. This is a completely different fan that is at the back of the oven itself.

The cooling fan is necessary as the materials in modern ovens are kept light and thin as possible to save weight and manufacturing costs, however the flipside of this is that if not cooled by the cooling fan, they would be damaged by the heat inside the oven itself.

The cooling fan will continue to run for some time after the oven is switched off, because it will wait until the oven has fully cooled down before stopping the cooling fan.

3 to 4 hours is a long time. Get to the fans (behind the control panel) and check the screens for dust. Chances are the screens are clogged with dust and need to be cleaned so the fans can move air for cooling better. I had this problem on my GE JTP14, and after cleaning just one fan it can keep up with cooling the electronic area while the oven is running. It runs much less often.

Safety first! cut the breaker before removing anything with a nice conductive screwdriver! Hope this helps!

try to open the door see if the door latch is extended if it is locate the light switch on the oven cavity and hold it in then hit start then cancel or stop the latch rod should go back

not sure of location but either on roof of oven or at the back close to the fan, but there is a fan start stat that turns the cooling fan on and off. could be stuck in on mode. only cure is to replace