Bosch smu 7056 uc Dishwasher problem
#1

My bosch dishwasher is about 6.5 years old. It acts as if there is no power going to it and it won't start, no lights, etc. It did this once before about 2 months ago then magically started working again after a few days. Circuit breaker is good. I pulled the front panel off, and the cover over the household wires supplying power. I used a regular light up volt tester. I've got power coming in off the house wires. When I check the wires near the switches , sometimes I get a dim light, other times it is not lighting. I checked both sides of the door switch, and the same thing. Sometimes it lights up other times not. So I'm stumped. No broken wires that I can see. Power coming into the unit is fine, power is intermittently getting broken or reduced somewhere in the unit. Any ideas? All advice is greatly appreciated!!!!
#2
Join Date: Feb 1998
Location: The Shake and Bake State USA
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Hello: ksorce
Voltage testers using a light to indicate current, in my opinion, are not as reliable as a volt meter. Surface current will light up the testers light.
Surface current (current that's there but not from the original source) will not run the appliance. Surface current may be comming from any other source in the house. Often can be determined to be present with a lamp and a small wattage bulb.
Might try this. Use an approved appliance extension cord to another power source to run the washer and determine if it operates correctly.
The power problem may not be in the dishwasher at all. May be a defective recepticule or bad circuit wall outlet, wiring to it where it connects to the wires in the back of the outlet recepticule and or breaker switch, etc.
Point here is not to assume the dishwasher is the cause since the problem does not happen all the time or everytime. Loose wires and bad recepticules cause those types of problems too.
Check back on your question several more times. Other members posting replies in this forum topic may offer you additional advice, ideas, suggestions, test and or repair methods.
Use the reply button to add additional information or questions. Using this method moves the topic back up to the top of the list automatically.
Regards & Good Luck. (Helping out in this forum topic)
Sharp Advice. TCB4U2B2B Business Management Services. Web Site Host, Forums Monitor & Multiple Topics Moderator. Energy Conservation Consultant & Natural Gas Appliance Diagnostics Technician.
Personal Reminder:
Buckle Up & Drive Safely.
"The Life You Save, May Be Your Own."
Voltage testers using a light to indicate current, in my opinion, are not as reliable as a volt meter. Surface current will light up the testers light.
Surface current (current that's there but not from the original source) will not run the appliance. Surface current may be comming from any other source in the house. Often can be determined to be present with a lamp and a small wattage bulb.
Might try this. Use an approved appliance extension cord to another power source to run the washer and determine if it operates correctly.
The power problem may not be in the dishwasher at all. May be a defective recepticule or bad circuit wall outlet, wiring to it where it connects to the wires in the back of the outlet recepticule and or breaker switch, etc.
Point here is not to assume the dishwasher is the cause since the problem does not happen all the time or everytime. Loose wires and bad recepticules cause those types of problems too.
Check back on your question several more times. Other members posting replies in this forum topic may offer you additional advice, ideas, suggestions, test and or repair methods.
Use the reply button to add additional information or questions. Using this method moves the topic back up to the top of the list automatically.
Regards & Good Luck. (Helping out in this forum topic)
Sharp Advice. TCB4U2B2B Business Management Services. Web Site Host, Forums Monitor & Multiple Topics Moderator. Energy Conservation Consultant & Natural Gas Appliance Diagnostics Technician.
Personal Reminder:
Buckle Up & Drive Safely.
"The Life You Save, May Be Your Own."
#3
Update
Well, using a multi-meter, I get a 120V reading from the household wires coming into the unit. Also just to clarify, when I mentioned that this issue happened once before and after a few days the dishwasher started working again, that was only one time.
I checked with the standard voltage tester around the dishwash push button switch connections (on off, regular wash, etc) I get either no reading or a very dim light. I didn't want to use the multi meter here since I wasn't sure which wires were common or hot, so without a troubleshooting guide or schematic, I can't do much more troubleshooting without direction on what to test - HELP! A good review of everything inside reveals no loose or broken wires. I would bet the issue is the switch assembly, but since I am not getting voltage there it is tough to validate that. Also it is a $180 part so I do not want to go and replace it without knowing for sure that is the issue. Help!
I checked with the standard voltage tester around the dishwash push button switch connections (on off, regular wash, etc) I get either no reading or a very dim light. I didn't want to use the multi meter here since I wasn't sure which wires were common or hot, so without a troubleshooting guide or schematic, I can't do much more troubleshooting without direction on what to test - HELP! A good review of everything inside reveals no loose or broken wires. I would bet the issue is the switch assembly, but since I am not getting voltage there it is tough to validate that. Also it is a $180 part so I do not want to go and replace it without knowing for sure that is the issue. Help!
#4
Update 2
Although I don't have a troubleshooting flow shart or schematic, I have to assume the black and white wires coming up from the bottom of the unit (along with a few other colored or stripped wires) are the hot and common. I pulled the black and and white connectins off the bottom of the switch assembly and I'm not getting voltage here. Is there some other protection circuitry that the houshold leads are attached to before the switch gets power? What else should I check? Again, I have 120 - 123 volts at the terminals coming into the dishwasher.
#5

After further investogation, the black wire inside the dishwasher that connects to the terminal where the household wires come in is the same wire that is routed to the on / off and wash switches. I was not getting 120V at the switch. After tracing the wire down to the bottom of the dishwasher I cut open the flat plastic sheath that protects the wires as they come under the bottom of the door. Sure enough there was a small burn spot on the black wire right where it bends back and forth with the door opening. Upon closer inspection the sheath has sort of threads sewn across it to hold it in place, and one of the threads went right through the wire, weaking it from the day it was made. When I pulled on the wire it broke apart instantly. There was enough slack so I pulled the wire up soldered and heat shrank the new connection, recovered everything and it works like a charm! Best of all it didn't cost a dime, and I was ready to go buy a new dishwasher!
#6
Join Date: Feb 1998
Location: The Shake and Bake State USA
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Hello: ksorce
Some suggestions which may be helpful:
The only positive proof any part is functioning correctly, is to carefully remove the part or parts you suspect to be the potential problems. Have the local appliance parts store person test it or check it. Appliance parts dealers carry replacement parts for all appliances and are listed in the phone book under appliances.
The do-it-yourself person can do electrical tests and continuity tests on several electrical parts. However, I do not recommend relying solely on either tests to determine if any electrical or electronic part or parts are causing the problem.
Links which may be helpful:
Electric Dryer Help Pages: (Copy & Repaste into your browser)
http://forum.doityourself.com/showthread.php?postid=555421#post555421
DIY'S Electric Appliances Pages:
Dishwasher, Dryer, Freezer, Refrigerator, Washing Machines & Info. http://doityourself.com/appliance/index.shtml
http://links.doityourself.com/links/appliances/
http://links.doityourself.com/
http://links.doityourself.com/links/appliances/
Read the manufacturers online web site for problem possibilities, solving methods, repair procedures, pictorials, downloadable repair manuals, etc which may be available online.
Search the manufacturers web site for a downloadable version of the owners or service manual. The file will be a pdf file opened with Adobe, which also needs to be downloaded first but worth having once obtained.
Retail appliance parts dealers can also help determine what the possible problem may be. Bring the make, model and serial numbers. Appliance part stores and dealers are listed in the phone book.
Check back on your question several more times. Other members posting replies in this forum topic may offer you additional advice, ideas, suggestions, test and or repair methods.
Some suggestions which may be helpful:
The only positive proof any part is functioning correctly, is to carefully remove the part or parts you suspect to be the potential problems. Have the local appliance parts store person test it or check it. Appliance parts dealers carry replacement parts for all appliances and are listed in the phone book under appliances.
The do-it-yourself person can do electrical tests and continuity tests on several electrical parts. However, I do not recommend relying solely on either tests to determine if any electrical or electronic part or parts are causing the problem.
Links which may be helpful:
Electric Dryer Help Pages: (Copy & Repaste into your browser)
http://forum.doityourself.com/showthread.php?postid=555421#post555421
DIY'S Electric Appliances Pages:
Dishwasher, Dryer, Freezer, Refrigerator, Washing Machines & Info. http://doityourself.com/appliance/index.shtml
http://links.doityourself.com/links/appliances/
http://links.doityourself.com/
http://links.doityourself.com/links/appliances/
Read the manufacturers online web site for problem possibilities, solving methods, repair procedures, pictorials, downloadable repair manuals, etc which may be available online.
Search the manufacturers web site for a downloadable version of the owners or service manual. The file will be a pdf file opened with Adobe, which also needs to be downloaded first but worth having once obtained.
Retail appliance parts dealers can also help determine what the possible problem may be. Bring the make, model and serial numbers. Appliance part stores and dealers are listed in the phone book.
Check back on your question several more times. Other members posting replies in this forum topic may offer you additional advice, ideas, suggestions, test and or repair methods.
#7
Member
Join Date: Mar 2009
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I have the same problem
Ksource,
looks like I have the same problem. I have a bosch dishwasher (smu7056uc) that has the indicator light (on/off switch in control panel) come on but does not run. Do you have any pictures or other ideas to help me troubleshoot? Should I unscrew the access panel and take a look at the wires?
Thx.
looks like I have the same problem. I have a bosch dishwasher (smu7056uc) that has the indicator light (on/off switch in control panel) come on but does not run. Do you have any pictures or other ideas to help me troubleshoot? Should I unscrew the access panel and take a look at the wires?
Thx.
After further investogation, the black wire inside the dishwasher that connects to the terminal where the household wires come in is the same wire that is routed to the on / off and wash switches. I was not getting 120V at the switch. After tracing the wire down to the bottom of the dishwasher I cut open the flat plastic sheath that protects the wires as they come under the bottom of the door. Sure enough there was a small burn spot on the black wire right where it bends back and forth with the door opening. Upon closer inspection the sheath has sort of threads sewn across it to hold it in place, and one of the threads went right through the wire, weaking it from the day it was made. When I pulled on the wire it broke apart instantly. There was enough slack so I pulled the wire up soldered and heat shrank the new connection, recovered everything and it works like a charm! Best of all it didn't cost a dime, and I was ready to go buy a new dishwasher!