Overcrank -- Engine Cranked But Failed to Start
The GENERAC-1100 (Generac Evolution) diesel fault code means: Overcrank -- Engine Cranked But Failed to Start. This is a serious severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- easy
A $30 car code reader can't do diesel. The HD7000 reads full-system codes and does parked DPF regen, idle/speed-limit, and service resets from the cab — on everything from a 6.7 Cummins/Power Stroke/Duramax pickup to Class-8 trucks (Detroit, Paccar, CAT, Volvo, Mack, International).
Check Price on AmazonAffiliate link -- we earn a commission at no extra cost to you.
Full-system 6/9/16-pin diesel scan tool for Cummins, Paccar, CAT, Detroit and more — plug-and-play, no subscription. A cheaper way to read heavy-duty codes a basic OBD2 scanner skips entirely.
Check Price on AmazonAffiliate link -- we earn a commission at no extra cost to you.
Common Symptoms
- Generator displays code 1100 on the Evolution controller panel
- Yellow alarm LED is solid or the panel shows a warning banner
- Generator fails to crank or start during weekly exercise cycle
- Engine cranks through the full crank cycle but does not start
Probable Causes (Ranked by Likelihood)
- Fuel supply shut off or exhausted -- gas valve closed, empty LP tank, or utility gas interruption Very Likely
- Low fuel pressure to the regulator or a stuck fuel solenoid preventing fuel from reaching the engine Likely
Step-by-Step Diagnostic Procedure
Confirm the fuel supply: manual gas shutoff open, LP tank has fuel, utility gas service on; then verify the fuel solenoid clicks during crank.
Common Fixes by Vehicle
What techs usually find when diagnosing GENERAC-1100 on specific platforms — tap a platform for the fix and the exact part:
Generac Guardian 7-26kW (Evolution 1.0/2.0 controllers) Easy DIY
Generac code 1100 (Low Battery) trips when controller voltage drops below ~12.0V. The factory-installed Group 26 battery typically lasts 2-3 years in outdoor enclosures and is the #1 cause of failed weekly exercises. Replace with a fresh Group 26R (or 26 in some kits) and verify the trickle charger reads 13.5-14.0V at the battery terminals after a full charge cycle. If the new battery dies again within 60 days, the charger is bad ($90-$150 part).
Labor: 20-30 minGenerac PowerPact 7.5kW Easy DIY
PowerPact units use a small Group U1 battery that is even more sensitive to cold. If 1100 returns after a battery replacement and the charger tests good, check for parasitic draw at the battery cable lug -- corroded copper between the terminal and the cable end is common in coastal installs. Clean with a wire brush, apply dielectric grease, and re-torque to spec.
Labor: 30-45 minFrequently Asked Questions
What does Generac code 1100 mean?
Code 1100 (Overcrank) means the engine turned over through its full crank cycle but did not start and run. The controller stops cranking to protect the starter rather than cranking indefinitely.
Can my generator still run with this code?
Not until the cause is found and cleared. The controller will not continue cranking once the overcrank limit is reached, so the generator will not start in AUTO until the fault is addressed.