Home›Controllers›Decision-Maker 3500

Decision-Maker 3500 Controller

The Decision-Maker 3500 is a generator-set controller. It is used on generator sets from Kohler, including the 100EFOZ, 100REOZJ4, 11EFKOZD and 11EKOZD.

118
Generator sets
Kohler
Brand
5–500 kW
Power range
4
Fuel types

Troubleshooting

37

Fault codes

CodeMeaningRemedy
32High Coolant Temperature
32AEmergency StopReset the emergency stop switch.
40Pre High Coolant Temp.
41Pre Low Oil PressureCheck and adjust oil level or replace oil pump.
48Emergency Stop
62Low Battery Volts
63Low FuelRefuel the generator set.

Symptoms & remedies

SymptomCauseRemedy
Battery charger and/or block heater not functioningDevices not connected to receptaclePlug devices into respective receptacles
Cranks but does not startController and Emergency Stop Switch
Display is blackNo/low battery chargeRecharge/replace battery
Display locks upNo/low battery chargeRecharge/replace battery
Display shows an error messageController firmware or pushbutton/rotary selector dial entry errorReview the System Fault Shutdown Lamp With Digital Displays section
Display shows single segmentLow battery voltageRecharge battery
Displays error message/locks upController master control buttons inoperativeReplace the controller master control button circuit board.
Does not crankController and Emergency Stop Switch
Duplex circuit breaker(s) tripped or trips when resetCircuit breaker overloadedReduce circuit load. Reset duplex circuit breaker(s).
Duplex receptacles have no powerGenerator set not runningPower to duplex receptacles is from the generator set—not shore power.
Excessive or abnormal noiseVibration excessiveTighten loose components.
High fuel consumptionCompression weakCheck the compression.
Lacks powerAir cleaner cloggedClean or replace the filter element.
Low Coolant Temperature (LCT) fault alarms occur even when a block heater is installed and properly functioning.The LCT sender was installed in the incorrect location on the unit. In this case, the sender was installed in a tee fitting on the return line from the engine block to the block heater. The correct LCT location is in the thermostat housing.
Low oil pressureOil level lowRestore the oil level. Inspect the generator set for oil leaks.
Main circuit breaker(s) tripped or trips when resetCircuit breaker overloadedReduce circuit load. Reset circuit breaker.
No or low output voltageVoltage regulation inoperativeReplace the junction box sensing fuses. If the fuse blows again, troubleshoot the controller.
Output voltage rampsDefective exciter windingTroubleshoot alternator components
Output voltage unstableVoltage regulation calibration incorrectReadjust voltage regulation
OverheatsGovernor inoperativeAdjust the governor.
Starts hardController faultTroubleshoot the controller.
Stops suddenlyEngine overloadReduce the electrical load. See the generator set spec sheet for wattage specifications.
The LCT sender/switch at the tee of the return line between the engine block and block heater has two terminals, indicating it is an incorrect sender/switch.Order LCT sender GM39458. Go to step 1.3.
Tow vehicle and trailer are unstable or noisy during brakingTow vehicle brakes wornCheck brake fluid level. Add fluid as necessary.
Trailer is unstable or noisy during towing.Tire(s) worn or damagedCheck tire condition. Repair or replace.
Unable to change voltage and current calibrationsCalibration not enabledEnable calibration in Generator Metering section 2.6.3 Calibration Submenu
Unable to find volt select menuVolt select not enabledEnable volt select in SiteTech
User-supplied wiring between customer connection panel and load devices feels hot or has burning odorWiring undersized for applicationContact onsite electrician or rental distributor.
Voltage selector switch knob does not rotate.Padlock installed on lockout featureContact onsite electrician or rental distributor.
Voltage selector switch position does not match load voltage.Unit not set up for applicationContact onsite electrician or rental distributor. See Section 3, Electrical Connections and Requirements, for more information.

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.