John Deere 001321.16 – Engine Control Unit (ECU) or primary vehicle control unit: Issue With Neutral Start Relay On Engine, Engine Cranking For Too Long

The system has identified a problem related to the neutral start relay on the engine, which is causing the engine to crank for an extended period. This indicates an issue within the starting circuit or the neutral start safety system, which manages the start sequence to prevent the engine from cranking unless the transmission is in neutral or park. An extended cranking time suggests that while the starter is engaging, the engine is not firing up as expected, which could be due to a malfunctioning relay, safety switch, or a secondary fuel delivery issue.

1. 1

   Check battery and connections: Ensure the battery is fully charged and terminals are clean and tight. Inspect for corroded or loose connections at the battery, starter, and engine ground strap.

2. 2

   Verify safety interlock switches: Check the functionality of the neutral start switch (often on the transmission), PTO switch, and seat switch.

3. 3

   Test starter relay and solenoid: Listen for a distinct 'click' from the starter solenoid when turning the key. If it clicks without cranking, test the starter by carefully jumping the large terminals on the starter relay (ensure the tractor is in park).

4. 4

   Check the fuel system: If the engine cranks but does not start, check for fuel in the tank and filter bowl. A long crank time after sitting can indicate the fuel system is losing its prime due to a small leak or faulty check valve.

5. 5

   Test the neutral start switch: Use a test light or multimeter to check for voltage at the switch's electrical connector when the key is turned to the 'crank' position. If voltage is present on one terminal but not the other when closed, the switch may be faulty. As a temporary diagnostic measure, the terminals can be jumped with a wire to see if the engine cranks normally, but this should be done with extreme caution, ensuring the transmission is in park.

1. 1

   Safety First

   Disconnect the negative battery cable to prevent accidental starting.

2. 2

   Locate the Component

   Identify the location of the neutral start switch (typically on the transmission housing) or the starter relay (often near the starter motor).

3. 3

   Disconnect and Remove

   Disconnect the electrical connector from the faulty component. Remove any mounting hardware and take out the old switch or relay.

4. 4

   Install New Component

   Install the new part, ensuring it is securely mounted.

5. 5

   Reconnect

   Attach the electrical connector to the new component.

6. 6

   Test

   Reconnect the negative battery cable and test the starting system to ensure the issue is resolved.