Generator Repair Services
in Gallatin, TN
A standby generator that fails to start during a Middle Tennessee blackout provides false security. Whether your unit is showing a red warning light, throwing error codes, cranking slowly, or failing to transfer power to your home, our licensed electricians diagnose and repair Generac, Kohler, Briggs & Stratton, and Cummins generators across Gallatin.
Expert Generator Fault Diagnosis & Repair in Gallatin, TN
A standby generator combines a precision combustion engine, an alternator, an automatic voltage regulator (AVR), a 12V starter battery charging circuit, and an Automatic Transfer Switch (ATS) linked to your main electrical panel. When your generator trips a breaker, flashes an alarm LED, or fails a weekly exercise run, identifying the root cause requires specialized diagnostic equipment and deep electrical expertise.
Our licensed electricians pinpoint electrical and control subsystem failures on all major brands including Generac Guardian, Kohler Standby, Briggs & Stratton, and Cummins Onan. We carry common OEM replacement components on our service trucks to resolve most generator issues on the initial visit.
Generator Repair Cost & Diagnostic Pricing in Gallatin
We provide straightforward, upfront pricing with no surprise charges. Here is what typical generator diagnostic and repair services cost in Sumner County:
Standby Generator Repair & Service Pricing
| Repair Service | Typical Symptom | Estimated Cost |
|---|---|---|
| Standard Electrical Diagnostic | Fault codes, weekly test failure, warning lights, surging | $125 – $225 |
| 12V Starter Battery Replacement | Clicking sound, slow cranking, dead battery error (Code 2100) | $175 – $285 (installed) |
| Automatic Transfer Switch (ATS) Repair | Generator runs but house stays dark; won't switch back to grid | $250 – $650 |
| Automatic Voltage Regulator (AVR) Repair | Low voltage, high voltage spikes, lights flickering under load | $275 – $550 |
| Controller Board & Sensor Replacement | Blank screen, false overcrank/overspeed codes, stepper motor fault | $350 – $850 |
| Annual Preventative Tune-Up | Routine synthetic oil, filters, spark plugs, load test | $180 – $350 / year |
Common Generator Failures We Diagnose & Fix in Gallatin
- Dead 12V Starter Battery (70%+ of No-Starts): The #1 reason a generator fails during a Gallatin storm is battery sulfation. We test Cold Cranking Amps (CCA) under load and verify the onboard float charger is delivering correct trickle voltage.
- Automatic Transfer Switch (ATS) Contactor Failure: If the generator engine starts but your house power doesn't turn on, the ATS coil or microswitch contacts may be stuck or burned. We test and repair 100A and 200A transfer switches.
- Generac & Kohler Fault Codes: We plug into digital control panels to read and clear fault logs (Overcrank Code 1100, Overspeed Code 1200, Low Oil Pressure Code 1300, RPM Sense Loss Code 1500, Undervoltage).
- Engine Runs But No Power Output: Caused by a tripped field circuit breaker, broken rotor brushes, or a failed Automatic Voltage Regulator (AVR).
- Fuel Solenoid & Stepper Motor Hunting: Engine revs up and down erratically under load due to gummed fuel stepper mixers or faulty governor actuators.
Our Generator Repair Services
Starter & Battery Diagnostics
Testing battery health under real load, replacing dead starter batteries, and repairing faulty trickle-charger circuits.
Automatic Transfer Switch Repair
Repairing ATS coils, sensing wiring, contactor mechanisms, and smart load-shedding modules for safe power transfer.
Controller & AVR Replacement
Replacing failed Automatic Voltage Regulators (AVR) and digital control boards to restore stable, clean 240V/120V household power.
Full Post-Repair Load Testing
We test every repaired generator under simulated utility blackout conditions to verify 100% reliability before leaving your property.