Mitsubishi Electric
Mitsubishi Servo Amplifier Repair (MR-J2S / MR-J3 / MR-J4, MDS) — Mail-In
Component-level repair for Mitsubishi servo amplifiers: the massive MR-J2S installed base plus MR-J3, MR-J4, and MDS CNC drives. Free evaluation, firm quote, typical repairs $450–$950.
Coverage: MR-J2S (10A–700A, A & B) · MR-J2 · MR-J3 · MR-J4 · MDS series CNC drives
✓Fixed — or it's free
Unrepairable units are refunded; evaluations cost $0
✓24-month warranty
Every repair covered, parts and labor
✓3–5 business days bench time
Rush (1–2 day) and emergency service available
✓Program preserved
Your application and settings stay in the unit
Symptoms this repair fixes
- ✓AL.32 / overcurrent class alarms
- ✓AL.10 undervoltage, AL.30 regeneration faults
- ✓Dead amplifier — no display
- ✓Trips breaker at power-on
- ✓Encoder communication alarms traced to the amp
Honest limits
- ✕Motor and encoder failures (identified at evaluation before you spend anything)
What you get
- ▸Free bench evaluation and firm quote
- ▸IPM (intelligent power module) replacement with new parts
- ▸Control power-supply and encoder-interface repair
- ▸Full recap as standard
- ▸Powered verification with a test motor where applicable
- ▸24-month warranty
Your program is safe
We preserve amplifier parameter sets where they are stored in the unit, and note anything your integrator should verify at reinstall.
Common part numbers we see
Part-number pages for this service
What to ship
- ▸The amplifier only
- ▸The alarm code and machine make/model
Full packing guidance: mail-in instructions.
Ship your unit to
USPS
Control Board Lab
PO Box 120241
Arlington, TX 76012
UPS / FedEx
Control Board Lab
1009 Oakwood Ln # 120241
Arlington, TX 76012
Write your RMA number on the outside of the box and include it on a note inside. Units over 50 lb (large VFDs, spindle drives, industrial PCs in enclosures) ship by freight — contact us before ordering and we will arrange dock-to-dock shipping.
Frequently asked questions
MR-J2S is obsolete — should I repair or migrate to MR-J4?
Migration means new motors or adapter engineering, parameter work, and downtime. While a machine otherwise runs well, repairing the failed amp (typically $450–$950) is dramatically cheaper. We'll tell you honestly at evaluation if your unit is at the end of its economic life.
What does alarm AL.32 usually mean?
AL.32 is an overcurrent fault — most often a failed IPM power module in the amplifier, sometimes triggered by a shorted motor or cable. Our bench evaluation isolates which. The IPM replacement is the bread-and-butter MR-J2S repair.
Start with a free evaluation
Ship it in, get a firm quote, approve before any work — pay nothing if it can't be repaired.
The Fixed-or-Free Guarantee: if we can't repair it, you don't pay for the repair.
Call (817) 799-7332 · 📱 Text us a photo of your unit · Email repairs@controlboardlab.com