Brand: Bosch Model Number: SHP65T55UC/07 (Series 500) Main Symptom: What happens & when: Two faint clicks and then error code.
Error Code (if any): E20
Parts or tests already tried: Checked for drain blockage but all clear. Suspect Circulation Pump as per Bosch error code.
Photos / video link: All looks good as no water leaked, no corrosion and no visually burnt parts
Hi! I have a Bosch Dishwasher SHP65T55UC/07 with Error E20. I have checked my hoses and drain compartment for blockages and it is all clean. There was some water stuck in the drain area when the error occurred the first time but I have since dried it with a towel. After power unplug, reset and re-attempt or even drain cycle attempt, there is a faint 2-click noise and then the error E20 resurfaces. I opened the Dishwasher and saw no visible damage, water, corrosion or anything suspicious. I read that there could be a faulty Circulation Pump issue. What do you recommend I do? I have a multimeter I could use. I saw there is a Test Mode menu. Is it any useful to troubleshoot this issue? If I order the part and it does not fix the issue, can I send it back?
BTW, I read in another forum that if the impeller does not show resistance, it could be a sign of damage. I am not sure if this is normal but mine shows zero resistance when spin manually:
The error E20 is going to indicate an issue within the heat pump circuit, which could be the circulation pump, wire harness, or the power control module. If you turn off the power supply to the dishwasher and access the 4-wire connector on the top corner of the power control module, the heater can be tested for resistance. The two red wires and the green wire directly next to the red wires would be tested for resistance to each other and should measure around 15 Ohms. If the resistance is not around 15 Ohms and there is not a damaged wire, the circulation pump would need to be replaced. If the resistance is around 15 Ohms each time, the power module would be the likely cause. Usually, the issue is the circulation pump though. https://www.appliancepartspros.com/bosch-heat-pump-12008381-ap5984938.html
Thanks for the quick and detailed reply. I am an IT professional and not afraid to tinker with personal computer equipment but certainly not very experienced with large appliances. I had gone as far as removing the front bottom cover of the Dishwasher. Am I required to remove the Dishwasher from the cabinet to perform the testing you suggested? If you have further guidance such as pictures, videos or diagrams of the components/cables where to set the multimeter probes, that would be very helpful. Otherwise I’ll search the Internet and if/when I find additional relevant information, I will post it here for the benefit of the board members.
That is the exact connector for testing and the dishwasher would need to be pulled out just enough to access this control connection. The power supply to the dishwasher will need to be turned off and the wire connector removed from the control. The wires on the connector would be tested. From left to right, the wires can be considered red 1, red 2, green 3, green 4. A multimeter would need to be set to Ohms or the omega symbol (upside-down horseshoe). The specific setting would depend on the meter as some are autoranging while others have different operational resistance settings. The probes would then be placed in this manner: 1-2, 1-3, 2-3. Are the resistance readings around 15 Ohms?
Thank you so much. I will test as per your instructions and let you know my results. I might not be able to do this until a few days out but I am excited that I have the proper plan and guidance from a reputable company and expert tech pro!
