The GSC400 Automatic Gen-Set is a generator-set controller. It is used on generator sets from DynaGen, including the GSC400.
| Symptom | Cause | Remedy |
|---|---|---|
| Fuel, Crank, and/or Extra Relay outputs are not turning on. | 1. Check that the proper relay (12VDC or 24VDC) is used based on the system voltage. 2. Check that the fuse beside each relay is not blown. | |
| GSC400 speed sensing terminals picking up stray signals during cranking | The GSC400 is sensitive to low voltages and frequency readings of 50/60Hz can cause it to think the generator has started. | 1. Check that there are no breakers off. 2. Check AC voltage and frequency during cranking. 3. Install an isolation transformer. |
| High Engine Temperature or Low Oil Pressure not reading correctly | 1. Confirm that the sender is connected to the correct input pin terminal. 2. Check wiring for continuity. 3. With the generator not running, unplug the sensor (analog inputs) plug from the controller and measure DC voltage on GSC400 terminal. 4. Plug the sensor connector back in and measure DC voltage from output of the sensor to battery negative. 5. Disconnect the sensor plug again and measure resistance from pin on the plug to battery negative. | |
| High Engine Temperature or Low Oil Pressure not reading correctly. | 1. Confirm that the sender is connected to the correct input pin terminal. Check the wiring for continuity. Check that the GSC400 is setup correctly in the advanced menu. 2. With the generator not running, unplug the sensor (analog inputs) plug from the controller. It’s the 2x4 pin connector on the bottom. On the GSC400 sensor terminal, measure the DC voltage of the input pin to battery negative. Do this on the GSC400 terminal, not the plug. It should read 5VDC. If it does not, there may be a problem with the controller. 3. Plug the sensor connector back in. You may need to do this step with or without the generator running. Look at the display on the GSC400 and note the value displayed. Then measure the DC voltage from the output of the sensor to battery negative. Note the reading. Lookup the pressure or temperature value using this voltage in the tables below. If it matches the value displayed on the GSC400 then the sender may be bad. If it does not, there is an issue with the wiring or setup or the controller may be bad. 4. Disconnect the sensor plug again and measure the resistance from the pin on the plug to battery negative. Refer to the below tables. Does the value from the table match the expected value? If not, the sender or wiring may be bad. | |
| High Engine Temperature reads around 1300F | Set to “Dat Pin2” (firmware 2.04.06 and higher) and change sender to pin 2. For firmware 2.04.03 and below set signal source to pin 2, and then once this is done program the “DatCon K – LowZ” to the controller using the GSC400 programmer and PC configurator. | |
| High Engine Temperature reads around 1300F. | This is normal when engine temperature is set to pin 3 or 4. | Set to “Dat Pin2” (firmware 2.04.06 and higher) and change sender to pin 2. For firmware 2.04.03 and below set signal source to pin 2, and then once this is done program the “DatCon K – LowZ” to the controller using the GSC400 programmer and PC configurator. The high engine temperature will then read down to 720F. |
| Speed is zero, generator won’t stop cranking. | Speed 1 and 2 terminals (J17, J18) need to be connected to generator output. | |
| Turns off starter prematurely or does not turn on starter and then goes into a low speed or low AC voltage failure without starting the generator. | 1. Check that there are no breakers off. This can unload the GSC400 sensing inputs allowing the wiring to act as an antenna. 2. Check the AC voltage and frequency during cranking. If it reads a few volts then it is likely the GSC400 is picking this up. If the frequency reads 50/60Hz, then the controller will assume the generator has started already. Try another L-L or L-N connection. 3. If necessary, install an isolation transformer to prevent stray signals. |
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.