The Printed Circuit Board (PCB) is a generator-set controller. It is used on generator sets from Generac, including the GPS 17500.
Also fitted to: Generac GPS 12500 (004451, 004986), Generac GPS 15000 (004582, 004987, 005209).
| Code | Meaning | Cause | Remedy |
|---|---|---|---|
| F1 | 10 Amp Fuse (F1) Blowing | Fuse blows upon installation; fuse blows when running; fuse is good but blows when placed to start; start-run-stop switch wired incorrectly; start stop relay (SSR) bad; fuel solenoid bad; starter contactor relay bad; BCR1 and BCR2 wired incorrectly; battery charge rectifier 2 (BCR2) bad; wire 15 bad; wire 15B bad; wire 14 circuit bad; diode/resistor bad; fuel shutoff solenoid (FSS) bad; hourmeter (HM) bad; wire 167 bad | Install new 10 amp fuse; verify start-run-stop switch is wired correctly (see Figure 6-46, pg. 55); check fuel solenoid (Test 47) and starter contactor relay (Test 44); verify BCR1 and BCR2 are wired correctly; repair or replace wire 14; correct wiring; repair or replace; replace |
| Symptom | Cause | Remedy |
|---|---|---|
| Engine "Hunts" / Erratic Idle | TR1 & TR2 wiring bad; choke bad; spark bad; spark plug bad; ignition magnetos bad; valves bad; stepper motor operation bad; carburetion bad; engine miss apparent | Adjust or replace; repair or replace; replace printed circuit board; adjust / re-test; adjust or replace; acceptable running limits for the engine are between 59-61 Hertz |
| Engine Cranks But Will Not Start | No spark; fuel supply bad; fuel shutoff valve bad; idle control switch not in the "OFF" position; fuel pump bad; choke not pulled full out; start stop relay (SSR) bad; start stop relay wiring bad; spark plugs bad; ignition magnetos bad; wire 167 bad; carburetion bad; valve adjustment bad; flywheel key bad; engine/cylinder leak down test/compression test bad; fuel shutoff solenoid (FSS) bad; fuel shutoff solenoid voltage bad; stepper motor control bad; wire 18/shutdown lead bad | Pull choke full out; turn on; turn off; pull out; adjust and re-test; repair or replace FSS; repair or replace; replace; replace printed circuit board; replenish fuel supply; adjust or replace; repair or replace as necessary; refer to Engine Service Manual P/N 0E2081 for further engine service information |
| Engine Starts Hard and Runs Rough | Engine miss is apparent; low fuel; spark bad; fuel supply bad; fuel pump bad; choke position and operation bad; spark plug bad; ignition magnetos bad; carburetion bad; valve adjustment bad; flywheel key bad; engine/cylinder leak down test/compression test bad; stepper motor control bad | Replace spark plug; push in after starting; replenish fuel supply; adjust or replace; repair or replace as necessary; refer to Engine Service Manual P/N 0E2081 for further engine service information; adjust valves and retest |
| Engine Starts Then Shuts Down | Engine oil level low; oil pressure switch and wire 86 bad; start-run-stop switch (SW1) bad; start stop relay (SSR) not wired properly; stepper motor control bad | Replenish oil; replace switch; verify start stop relay (SSR) is wired properly; go to Problem 8 |
| Engine Will Not Crank | 10 amp fuse bad; fuse blows; battery & cables bad; voltage at starter contactor no voltage measured; starter contactor bad; starter motor bad; starter contactor relay (SCR) bad; start-run-stop switch (SW1) bad; start-run-stop switch (SW1) wiring bad; mechanical binding of the engine or rotor | Replace fuse; repair or replace wiring or SCR; recharge or replace battery - clean, repair or replace bad cable(s); replace; replace starter motor if defective; repair or replace wire 16; repair wiring; check for mechanical binding of the engine or rotor; go to Problem 9 |
| Excessive Voltage/Frequency Droop When Load is Applied | Load voltage & frequency bad; load watts & amperage overloaded; stepper motor control bad | Reduce load; go to Problem 8; end test |
| Frequency good - voltage high or voltage low | Go to Problem 3 | |
| Frequency good - zero or residual voltage | Go to Problem 2 | |
| Frequency is good, but no-load voltage is high or voltage is low | Go to Voltage Regulator Adjustment, Page 11; Test 5 - Check Stepper Motor Control | |
| Generator Produces Zero Voltage or Residual Voltage (2-12 VAC) | Main circuit breaker bad; excitation circuit breaker bad; excitation circuit bad; rotor amp draw bad; stator bad; excitation wiring bad; wire continuity bad; diode/resistor bad; field boost bad; sensing leads bad; brush leads bad; brushes & slip rings bad; rotor assembly bad | Reset to "ON" or replace if bad; repair or replace; replace voltage regulator; repair or replace, then retest; perform insulation resistance test page 13; perform insulation resistance test page 14 |
| Generator Produces Zero Voltage or Residual Voltage (2-12 VAC) (continued) | Voltmeter fuses bad; rotor amp draw bad; stator DPE winding bad; rotor assembly bad | Replace fuses - then retest; repair or replace; perform insulation resistance test page 13; perform insulation resistance test page 14 |
| Idle Control "RPM Does Not Decrease" | Stepper motor operation bad; idle control switch bad | Repair or replace; replace |
| Idle Control "RPM Does Not Increase When Load Is Applied" | Load on the generator; idle control wiring bad; idle control transformers (ICT) bad; wire 11 & wire 44 not routed through idle control transformers (ICT) | Verify that there is no load on the generator; replace printed circuit board; repair or replace; route through idle control transformers and re-test |
| No 10A Battery Charge Output | 10A battery charge output bad; battery charge rectifier bad; 10A circuit breaker bad; stator bad | Repair or replace; replace; perform insulation resistance test page 13 |
| No Battery Charge Output | Battery charge output bad; battery charge rectifier bad; stator bad | Repair or replace; replace; perform insulation resistance test page 13 |
| No-load voltage & frequency good - voltage/frequency falls off under load | Go to Voltage Regulator Adjustment, Page 11 | |
| Unit Overspeeds | No-load voltage & frequency bad; wires 11S/44S bad; red LED on circuit board is "ON"; stepper motor operation bad | Go to Problem 2; repair or replace; replace circuit board; replace |
| Voltage & Frequency Are Both High or Low | Go to Problem 1; Test 1 - Check No-Load Voltage & Frequency | |
| Zero voltage and zero frequency | Go to Problem 2 |
Fault codes and symptom→remedy steps extracted from this controller’s service/owner documentation; verify against the official manual before servicing. Aggregated from the service documentation of generator sets built on this controller.