Curtis Instruments — Leader in Electric Vehicle Controllers. When It Fails, the Vehicle Stops
Curtis Instruments (Livermore, California, USA) is one of the leading manufacturers of controllers for electric industrial vehicles — forklifts, AGV (Automated Guided Vehicles), warehouse platforms, golf carts, special vehicles, utility vehicles and electric construction machines. Curtis 1200, 1300 and 1500 series controllers manage traction motor power, regenerative braking, battery pack thermal protection and CAN J1939/CANopen communication.
A failed Curtis controller = an electric forklift stuck in the warehouse or an AGV production line without a vehicle = losses of €200–1,500/day. New genuine Curtis controller: €600–2,800, 3–10 weeks lead time. Our repair: 3–6 working days, €180–780.
Damaged Curtis controller? Call us — free phone diagnosis, quote same day. We ship and receive from all over Poland and Europe.
Curtis Controller Models We Repair
| Controller model | Voltage | Max current | Motor type | Application |
|---|---|---|---|---|
| Curtis 1207 | 12–36V | 90–275A | DC PM / Series | Small electric vehicles, platform carts, light AGVs |
| Curtis 1209 | 12–48V | 120–400A | DC PM / Series | Stackers, platforms, medium AMR/AGV |
| Curtis 1232 | 24–48V | 275A | DC PM / Sep-Ex | Electric counterbalance forklifts up to 2t — drive |
| Curtis 1234 | 24–48V | 350A | DC PM / Sep-Ex | Electric forklifts 2–3.5t — drive |
| Curtis 1236 | 36–80V | 400A | DC PM / Sep-Ex | Heavy electric forklifts 3–6t — drive |
| Curtis 1238 | 24–80V | 500A | DC PM / Sep-Ex | Large forklifts, airport platforms, special vehicles |
| Curtis 1314 | 24–80V | 600A | AC Induction | AC electric forklifts 3–8t, modern AGV/AMR |
| Curtis 1351 | 24–80V | 350A | AC Induction / PMSM | AC electric forklifts, PMSM AGV vehicles |
| Curtis 1510 | 24–80V | 500A | AC Induction | Heavy electric vehicles, airport tow tractors, industrial AGV |
Vehicles and Machines with Curtis Controllers
| Vehicle / machine type | Manufacturer / brand | Typical Curtis controller |
|---|---|---|
| Electric counterbalance forklifts | Linde E-series, Still RX 20/50, Jungheinrich EFG, Crown SC/FC, Hyster J-series, Yale ERP-series | Curtis 1234 / 1236 / 1238 |
| Reach trucks | Linde R-series, Still FM-X, Jungheinrich ETR, Crown ESR | Curtis 1232 / 1234 |
| Compact platform and pallet trucks | BT (Toyota), Crown WP, Raymond, Noblelift | Curtis 1207 / 1209 |
| AGV and AMR vehicles | KION (Dematic), Grenzebach, Swisslog, Knapp, Agilox | Curtis 1232 / 1314 / 1351 |
| Cleaning machines and sweepers | Nilfisk, Tennant, Hako, Comac | Curtis 1207 / 1209 / 1232 |
| Golf carts and utility vehicles | Club Car, E-Z-GO, Yamaha Golf Cars | Curtis 1207 / 1209 |
| Airport tow tractors and baggage vehicles | TLD, JBT, Charlatte, Tronair | Curtis 1238 / 1510 |
| Electric mining vehicles | Paus, Fermel, Normet, Sandvik (el.) | Curtis 1236 / 1238 / 1510 |
| Electric work platforms and lifts | Skyjack, Snorkel, Hy-Brid Lifts, Xtreme | Curtis 1232 / 1234 |
Common Curtis Controller Faults — Fault Codes and Symptoms
| Curtis fault code | Symptom | Cause | Repair |
|---|---|---|---|
| Fault 11 — Throttle Fault | No drive — "Throttle Pot Wiper High/Low" | Failed throttle potentiometer, failed ADC channel for throttle signal in controller | ADC diagnostics, potentiometer or ADC repair on PCB |
| Fault 15 — Main Contactor Driver Fault | Main contactor won't close, vehicle has no traction voltage | Failed MOSFET or bipolar driver for contactor coil output, failed TVS protection diode | Contactor output driver MOSFET replacement, TVS diode |
| Fault 21 — Current Sense Fault | Immediate stop on throttle — "Overcurrent" | Failed current sensor (Hall-effect LEM LA/LA-P), short circuit in drive bridge or traction motor | LEM sensor replacement, MOSFET bridge diagnostics, motor test |
| Fault 23 — Controller Overtemperature | Vehicle stops after several minutes of operation | Failed NTC temperature sensor in controller, loose heatsink, blocked vents, motor overload | NTC sensor replacement, heatsink cleaning, load verification |
| Fault 24 — Battery Voltage Low | No drive, vehicle shows low battery voltage | Discharged battery pack, failed voltage sensor in controller (ADC), loose battery + terminal | Voltage measurement circuit diagnostics, battery pack test |
| Fault 31 — EEPROM Fault | Controller won't start or behaves erratically after power loss | Failed EEPROM storing vehicle configuration (deep discharge below 18V erased memory) | EEPROM replacement, vehicle parameter reprogramming via 1311 Programmer |
| Fault 52 — Precharge Fault | Main contactor won't close — "Capacitor Precharge Failure" | Failed precharge circuit (resistor or relay), failed DC Bus capacitors in controller | Precharge resistor/relay replacement, DC Bus capacitor replacement |
| Fault 61 — Output Short Circuit | Immediate shutdown on throttle — "Armature Short" | Short circuit in motor armature winding or motor cable harness, failed H-Bridge MOSFETs | Motor diagnostics, H-Bridge MOSFET replacement |
| Fault 71–74 — Motor Sensor Faults | Encoder/Hall sensor fault | Failed magnetic encoder on AC motor shaft, broken 5V encoder supply in controller | Encoder replacement, 5V encoder supply repair |
| No CAN J1939 / CANopen communication | Controller absent from network, no response to 1313/1314 tester | Failed CAN transceiver (TJA1050/MCP2551/SN65HVD230), wire harness break or short, missing 120Ω terminator | CAN transceiver replacement, CAN network diagnostics |
Pricing — Curtis Controller Repair
| Model / repair scope | Price |
|---|---|
| Curtis 1207/1209 — MOSFET H-Bridge repair | €180–380 |
| Curtis 1232/1234 — MOSFET H-Bridge repair | €220–480 |
| Curtis 1236/1238 — MOSFET H-Bridge repair 80V | €280–580 |
| Curtis 1314/1351 — IGBT/MOSFET AC bridge repair | €320–680 |
| Main contactor driver repair (Fault 15) | €120–280 |
| LEM current sensor replacement (Fault 21) | €120–280 |
| DC Bus precharge circuit repair (Fault 52) | €150–320 |
| CAN J1939 / CANopen transceiver repair | €120–280 |
| EEPROM replacement + configuration (Fault 31) | €150–320 |
| Throttle ADC repair (Fault 11) | €80–200 |
| DC Bus capacitor replacement | €150–350 |
| Full controller overhaul | €380–780 |
| Diagnostic without repair | €80 |
Repair time: 3–6 working days. Warranty: 12 months. Service Mon–Fri 08:00–16:00. No-fix no-fee.