**Guangdong Longhong Electromechanical Equipment Co., Ltd. Answers for You:**  

**Fault Diagnosis Guide**  

**Diesel Engine Section**  

**Engine Cannot Be Turned or Cranking Speed Is Too Low**  

**Causes:**  

A) Insufficient battery charge  

B) Main switch is open  

C) One semi-automatic fuse in the terminal box has tripped  

D) Poor contact/open circuit in wiring  

E) Key switch failure  

F) Starter relay failure  

G) Starter motor failure  

H) Any other faults in the starting circuit  

I) Water ingress in the engine  

J) Low lubricating oil temperature  

K) Use of incorrect lubricating oil type  

L) Other internal or external factors affecting engine rotation  

**Remedial Measures:**  

A) Check the electrolyte level and top up if necessary. Charge the battery or replace it if required.  

B) Close the main switch.  

C) Press the button on the fuse to reset it.  

D) Eliminate any open circuits or poor contact issues. Check terminals for oxidation and clean if necessary.  

E) Replace the key switch.  

F) Replace the starter relay.  

G) Contact authorized personnel for assistance.  

H) Inspect all other starting circuits.  

I) Contact authorized maintenance personnel. Do not start the engine.  

J) Install an oil pan lubricating oil heater.  

K) Replace the lubricating oil and filter, ensuring the correct type of oil is used.  

L) Check if the crankshaft can be turned freely.  

**Foshan Generators | Guangzhou Generators — Guangdong Longhong Electromechanical Equipment Co., Ltd.**