John Deere 523677.07 – OIC / EPC: Declutch Switch on Range-Shift Lever (S158), Malfunction / Voltage Too High During Start-Up

The control software detects that the declutch switch on the range shift lever is activated during the starting procedure, while the range shift lever is not in the park position. The control software automatically turns off the function of the declutch switch on the range shift lever for safety.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6230
• 6330
• 6430
• 5080R
• 5090R
• 5100R
• 5080RN
• 5090RN
• 5100RN
• 6M Series
• 6R Series
• 6090MC
• 6090RC
• 6100MC
• 6100RC
• 6110MC
• 6110RC

1. 1

   Verify Operator Procedure: Confirm the operator is not resting their hand on or pressing the declutch switch while starting the tractor.

2. 2

   Inspect the Switch (S158): Check the physical condition of the gear stick button for sticking, missing pieces, or a collapsed internal spring.

3. 3

   Test Voltage Levels: Use a multimeter to measure the signal voltage in the declutch switch circuit to check if it is receiving constant system voltage without the button being pressed.

4. 4

   Check for Shorts: Inspect the wiring harness running down the shift lever and under the console for any rubbed-through insulation causing a short circuit to a positive voltage source.

1. 1

   Address Wiring/Switch Faults

   If the switch is physically stuck or tests faulty with a multimeter, replace the declutch switch/gear stick button. If the switch is fine, repair any identified short-to-power in the wiring harness.

2. 2

   Update Software

   Ensure the OIC/EPC control software is updated to the latest version, as firmware updates can improve the handling of declutch switch signals.

3. 3

   Reactivate the Function

   Manually reactivate the declutch function using a diagnostic tool by going into the control unit addresses and reactivating the function in address PTQ167 (or EPC167 depending on the module).

4. 4

   Clear and Test

   Clear the fault codes, restart the tractor without touching the shift lever, and test the declutch button during operation to ensure smooth range shifts.