Sevcon Service & Repair Forum

I have a 4 wheel drive bad boy buggies that i changed from lead acid to lithium and now the machine wont move . I get a code on my sevcon 633T45320 controler that indicates either the motor is bad or the contactors are bad. I ve replaced both and i still gat the code. Wondering if there is a reset that needs to be done?

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— Posted by Dan Brock on 2026-06-02

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If you need your Sevcon unit tested or repaired,
give us a call at 1-336-969-0110.
We offer free estimates and extended warranties on the work performed.
Shipping/Receiving:
Industrial Electronic Repair
145 Rockwell Place Ct
Tobaccoville, NC 27050
Phone: 1-336-969-0110


Recent 130 Comments

#Sevcon by HOSPITAL on 2012-11-02 09:45
Can the Sevcon MOS90 631/46002 Power Supply be repaired or bought? I'm trying to check this off my to-do list. Thank you!

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#Sevcon by James Dodds on 2013-06-17 10:16
The Sevcon MOS90 631/40277 power supply unit isn't working as reported.

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#Sevcon by Agustín Vega Yépez on 2012-01-08 01:43
Hello, I am interested in purchasing a Sevcon MOS90 631/46002 Power Supply. I am not entirely sure if this is the correct model, but my team suggested reaching out to inquire about pricing and availability. I am looking to source this unit quickly. Thank you.

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#Sevcon by Nosowicz on 2012-08-19 13:07
Can you please provide more information about the Sevcon MOS90 631/46002 power supply unit so I can check if it is still supported and if replacement parts are available?

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#Sevcon by Thanos Athanasiadis on 2012-01-28 21:12
Hello, I am reaching out regarding Sevcon MOS90 631/46002, which is a Power Supply unit. My client is experiencing issues with it and needs some information on repair services. Can you please provide details on troubleshooting and repair options available for this specific model? Thank you. —> …Purchase or Repair: Ticket Image...
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#Sevcontrol by it on 2013-08-06 19:32
My Sevcontrol MOS90 631/40164 power supply is malfunctioning and needs repair. Looking for a qualified technician to fix it as soon as possible. Thank you.

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#Sevcon by Premanku on 2012-03-24 09:23
I'm having trouble with the Sevcon MOS90 631/46002, specifically related to the power supply. I'm not entirely sure what the issue is, but something seems to have stopped working. Any guidance or support you can provide would be greatly appreciated.

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#Sevcon by Kristen N Utt on 2013-07-09 20:32
Sevcon MOS90 631/40277 is malfunctioning, affecting the power supply line. Please prioritize this issue with the repair service to ensure a swift resolution.

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#Sevcon by Ken Van Dyke on 2012-10-24 18:37
I need an update on the status of the Sevcon MOS90 631/46002 power supply. The unit is still down. Please provide a

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#Sevcon by Foor on 2013-02-24 10:59
Could the Sevcon MOS90 631/40277 power supply be repaired or purchased as a replacement? I'm working on checking this off my to-do list. Thank you!

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#Sevcon by peter coutts on 2013-02-01 16:53
I apologize for the inconvenience, but there seems to be an issue with the power supply unit of your Sevcon MOS90 631/40277. It's possible that this is causing the machine to stop working as expected. I recommend contacting a technician to diagnose and resolve the problem.

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#Sevcontrol by melanie hamilton on 2016-12-06 13:32
I am following up on my previous message regarding the Sevcontrol MOS90 631/40038 unit being down. It is crucial that someone addresses this issue

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#Sevcon by Bayu on 2012-09-19 19:15
The Sevcon MOS90 631/46002 unit appears to be a power supply. It is currently not functioning properly, and assistance from the maintenance team is needed.

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#Sevcontrol by Chinh on 2013-03-25 10:32
Hello, my client is having issues with a Sevcontrol MOS90 (part number 631/40164) related to the power supply. Can you provide information on troubleshooting steps or potential repairs for this? Thank you.

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#Sevcon by donnie rasnake on 2012-06-23 23:35
Can the Sevcon MOS90 631/46002 power supply be repaired or bought? I'm trying to address this on my to-do list.

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#Sevcon by MIKALEF on 2012-08-12 20:45
I'm experiencing issues with the Sevcon MOS90 631/46002 model related to the power supply. Something seems to have stopped working, and I'm unsure of the exact problem. Any assistance you could provide would be greatly appreciated.

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#Sevcon by Nguyen Tat Thang on 2013-08-04 02:32
The Sevcon MOS90 631/40277 unit is not working and is related to power supply.

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#Sevcon by shahnawaz on 2012-08-06 04:24
The Sevcon MOS90 631/46002 unit in the warehouse is behaving unusually. It's not functioning as expected, exhibiting erratic behavior.

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#Sevcon by persuno on 2012-01-16 09:36
My Sevcon MOS90 631/46002 power supply unit is not functioning properly. Looking for a tech who can repair industrial units like this.

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#Sevcon by Surma on 2015-01-10 23:41
I'm currently experiencing an issue with the Sevcon MOS90 631/41063 controller. I'm unsure of the specifics, but something seems to have stopped working. Any assistance would be greatly appreciated.

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#Sevcon by SHANE STOCKTON on 2012-02-17 15:52
One of the Sevcon MOS90 631/46002 drives or boards is down, affecting the power supply. Need immediate attention to diagnose and resolve the issue.

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#Sevcon by kurnianto on 2013-04-14 04:31
Can the Sevcon MOS90 631/40277 power supply be repaired or bought? I'm looking to check this off my to-do list.

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#Sevcon by GABON on 2012-06-11 07:05
Hello, our Sevcon MOS90 631/46002 power supply is displaying error code 3F. The equipment is not powering up at all. Kindly advise on troubleshooting steps. Thank you.

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#Sevcon by Marcel on 2026-05-13 10:34
Hello,my friends PCB burned out. Can you send me the PCB gerber data and possibly also the bill of materials? I can make a new PCB myself.ThanksMarcel

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#Sevcon by Breneman on 2012-05-29 19:30
I can assist you with finding information on the Sevcon MOS90 631/46002 Power Supply unit. I will inquire about its current support status and the availability of replacement parts for you.

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#Sevcon by Mika on 2012-10-20 00:57
The Sevcon MOS90 631/46002 is still down and I need assistance with the power supply. Please provide a response this time.

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#Sevcontrol by ANIL KUMAR P on 2013-08-04 01:32
Hello, I'm interested in purchasing a Sevcontrol MOS90 631/40164 power supply. I'm not 100% sure if this is the correct model, but my team suggested I reach out to inquire about pricing and availability. I'm looking to source one quickly. Thank you.

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#Sevcontrol by garces on 2013-08-11 00:35
The Sevcontrol MOS90 631/40164 power supply unit is not functioning as expected. It is exhibiting abnormal behavior that is unfamiliar to me.

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#Sevcon by David Simmons on 2013-08-15 01:01
Hey, the Sevcon MOS90 631/40277 power supply unit went down mid-shift. Needs attention ASAP. Thanks!

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#Sevcon by Ingram on 2012-02-07 00:32
Our Sevcon MOS90 631/46002 unit experienced a power supply issue causing downtime today at 345 PM. Need quick resolution before the next shift starts. Thank you.

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#Sevcon by David Barnes on 2012-03-16 13:47
Hello, I am inquiring about Sevcon MOS90 631/46002, which is a power supply. My client is experiencing issues with this part and would like to get more information on repair options. Thank you.

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#Sevcon by Arslan on 2015-01-10 07:41
The Sevcon MOS90 631/41063 controller is exhibiting abnormal behavior in the warehouse.

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#Sevcon by Kirk Niatsikas on 2012-01-10 16:30
: Our industrial unit is experiencing persistent issues with the hydraulic system in our production line. We have experienced multiple malfunctions, including incomplete processing of orders and production delays. The unit's hydraulic pressure control mechanism has been failing intermittently, causi…Purchase or Repair: Ticket Image...
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#Sevcon by SMAILL TABRIZI on 2015-08-14 02:20
Sevcon MOS90 631/41063 Controller not responding.

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#Sevcon by Swanson on 2013-12-30 16:27
Sevcon MOS90 631/40277 power supply is not providing power to the machine.

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#Sevcon by aziz fayek aziz on 2015-07-30 20:20
Hello, I hope you're doing well! I'm working on getting your Sevcon MOS90 631/41063 controller fixed or replaced. Before proceeding, would you please advise if it can be repaired or if a new one needs to be purchased? I'm aiming to check this off my to-do list as soon as possible. Thank you! —> …Purchase or Repair: Ticket Image...
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#Sevcon by DIEGO SCIUTTO on 2012-12-03 20:43
The Sevcon MOS90 631/46002 unit is not functioning properly and requires maintenance attention.

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#Sevcon by SHAIKH MUJJAFAR NAJIR on 2012-07-19 03:59
I'd like to inquire about the pricing and availability of the Sevcon MOS90 631/46002 Power Supply unit. My team recommended I reach out to you regarding this. I am hoping to source one quickly. Thank you!

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#Sevcontrol by Toll on 2013-03-16 09:15
I need assistance with repairing my Sevcontrol MOS90 631/40164 power supply unit. Our production is stalled, and I'm hoping you can provide a solution. Do you have a replacement unit available for sale or repair?

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#Sevcon by Edgar Rodriguez on 2013-03-16 20:15
My Sevcon MOS90 631/40277 is still down and in need of assistance. Please respond

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#Sevcon by Beamond on 2012-08-04 14:24
The Sevcon MOS90 631/46002 experienced a power supply issue, resulting in downtime. This occurred earlier today during the morning shift. I would appreciate a

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#Sevcon by Mohammad Tazuddin on 2013-08-15 12:01
Can the Sevcon MOS90 631/40277 power supply be repaired or bought? I'm trying to check this off my to-do list.

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#Sevcon by Tong Sheng Holdings on 2013-10-22 12:18
Can the Sevcon MOS90 631/40277 power supply be repaired or bought? Checking this off my to-do list.

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#Sevcon by BAYSDEN on 2013-07-30 15:32
Is the Sevcon MOS90 631/40277 still supported or are replacement parts available for repair?

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#Sevcon by McDaid on 2012-08-02 05:55
Hi there, can you provide repair information for a Sevcon MOS90 631/46002 Power Supply unit? It has stopped working and we need a replacement. Thank you.

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#Sevcon by Chrisman on 2012-10-28 21:03
Sevcon MOS90 631/46002 power supply not providing consistent voltage output.

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#Sevcon by Soliz on 2013-08-01 07:32
The Sevcon MOS90 631/40277 power supply unit is exhibiting unusual behavior in the warehouse. It is not performing its normal functions and appears to be acting erratic or strange. Further investigation is needed to identify and address the issue with this unit.

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#Sevcontrol by Tran Son Mai on 2013-07-17 15:55
Can the Sevcontrol MOS90 631/40164 power supply be repaired or bought? I'm trying to check this off my to-do list.

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#Sevcon by jean on 2013-04-04 23:28
Looking for someone to repair a Sevcon MOS90 631/40277 power supply unit.

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#Sevcon by Goeda on 2013-05-25 06:24
Can the Sevcon MOS90 631/40277 power supply be repaired or purchased? I'm trying to check this off my to-do list.

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Industrial Electronic Repair
145 Rockwell Place Ct
Tobaccoville, NC 27050
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Industrial Electronic Repair
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