sERVICEMANUAL

MedWrench is available to help people with specific questions and troubleshooting problems. Could you please be more specific with the issue that you are having with your instrument, and the MedWrench team will do their best to assist you in solving the issue. This will also help other community members who face similar challenges.

Midmark 75L exam chair issue - not working, hand control doesn't work

Hi Kari,

I recently purchased a Midmark 75L exam chair from auction. The chair is not working at all using the hand control provided with it. I initially thought that the hand control was faulty so I purchased brand new components based on the OEM number provided in the service manual. I bought new cord, membrane, and PC unit and assembled it for the hand control, however, there no light or function coming out of the hand control nor the chair. I check the chair main PC unit, tested all the 5 fuses and they appeared to be okay. I also tested the AC units attached to the chair, it has power. I used a power tester to test if there is power supply to the PC, i have some positive results as well. At this point, I don't know what may be wrong with the exam chair, if you could please help me with some leads. I am based in San Antonio Texas, zip code 78215.

Many thanks for your help.

Thanks,

Ade

Stephen,

I am about to submit this to our manual submission portal. The service manual for this model should be available under documents shortly.

Thank you Koby! This is much appreciated. The manual has been uploaded and can be found HERE.

75L is not a model number, there are a ton of chairs that full under this submodel.

on the mfr label on the back you will find the actual model and revision. That is what you will need fto obtain the correct manual.

if you have a 411, on the underside of the onboard controls is a kill switch. Midmark has used a number of different types of sensors, if any of those detect an error, it will shut off all or some functions.

Hello, thanks for your response.

I have a 411-014 JY1000 230 VAC with programming. Can you please upload the service manual? Also, is the kill switch on the right side of the base? I'll appreciate it if you can send me the service manual that would help me figure this out.

A copy of the 411 service manual can be found HERE.

I think this forum is great, I had a call on the 75L midmark on the foot section that would not function. we had a tech go out and trouble shoot the issue. Thank you all

that manual won't help you it's for a different revision, I sent the one you need to medwrnech a few minutes ago, give them a few days to upload it.  Midmark has made a number of their service manuals available on thier website as well.

The kill switch I had spoken about is only for revisions 001-008, your 014 doesn't have that feature.

Let's get back to troubleshooting,

Are you sure its a 230vac and not a 120vac? If it is a 230vac table(thoe are pretty unusal, most people have the 120vac models. the 230vac has a choke on the power entry module

You've verified there is 230vac to your main board and you've checked the 6 fuses on that main board, not just in the power entry module, correct? you earlier said you checked 5.

each function has it's own, and there are 2 for primary AC.

There are different models of hand controls for the 411. the one for your chair is 002-0604-00. Is that what you have? it's tear shaped, not the rectangular one. 

Where the hand control and foot controls plug in, there is an inlet board. If everything else checks out, this may be your culprit.

Let's start here, and let me know what you find. it's always possible you got a real dud and your main board is toast, or multiple components are dead. But i'll keep my fingers crossed for the simple culprit.

Thank you to Chris-CBET for the additional manual which can be found HERE.