My Kohler 12res won't start. It will try to start but the motor will crank for about 5 seconds or less, (turn about 1/8) and stop. The ADC 2100 controller will show cc1 during this start attempt go blank and try to start again. All 3 leds on the relay board will come on and go off. The unit will keep this up till you stop it. It does this in both auto and manual. 12 volt power is and stays good to both the relay board and controller. I can see the controller ground the fuel/run relay, then the crank relay. It just wont keep cranking enough to turn the motor completely around. The controller is new and supposed to have been checked by Kohler. It is supposed to have been programed by Kohler with my serial number. I can jump around the relay board or go straight to the controller plug and start the engine and it will run. I think the new controller is defective or wasn't programed right, but according to Kohler it is good. I haven't been able to get into the program mode to check the settings. I sure could use some help on this.

SOURCE: kohler 12res hunting and surging when running

hunting is usually caused by fuel starvation not an electronic fault

SOURCE: 12RES GEN.NAT.GAS FAILS TO START BY STRT BTTN AND TRNSFR SW

If the succession is 3-5 sec crank - 3-10 sec pause, it is OK, but the cranking is not successful (the reason should be investigated).
If the succession is more rapid 1 - 2 sec you may have bad PCB control.

SOURCE: Have Kohler 12RES. Gives a CC1 code thenan OC

check your load wires there probaly reversed. I had the same problem friday. The week before the electrican wired it. did the same cc1 then oc. had a generator company come out it was the wireing. my load and netural were reversed.

SOURCE: Kohler 12 RES - Unit fails to start occasionally. Attempting a manual start by placing switch in run position, cause a loud click, but no cranking. The panel says CC. This morning I put a jump star

I finally solved the intermittant starting problem on my Kohler 12 RES by replacing the strater and the starter relay. I was also experiencing the occassional OC indication, red blinking LEDs on the ATS, and intermittent non-starts during the weekly exercises. The problem happened during power outages a couple times also. If I flipped the start switch between auto and run quickly the generator would occasionally start. Once started, the generator runs fine. I ordered a new starter, which included the starter solenoid. By the way, don't worry about the genuine part thing..the old starter was a Delco made overseas. I ordered a new starter online for $85 (6744N) and it was indentical to the genuine Kohler starter. Replaced the starter and it improved the problem but did not totally solve the intermittent starting. Ordered the starter relay (GM49746) replaced it and the problem is solved.

SOURCE: Kohler 12RES only starts on second try

Check gas pressure. Oc is over crank. Means tried to start but did not.