John Deere 598.02 – PTR / TCU / EPC / PTA / PTP: Clutch Pedal Potentiometer and Clutch Pedal Switch, Signals Mismatch

The control unit detects conflicting data between two components: the clutch pedal switch indicates that the clutch is open (pedal fully depressed), while the clutch pedal potentiometer (position sensor) simultaneously reports a voltage value indicating the pedal is in the 'up' (released) position. This discrepancy triggers the code and often causes the transmission to enter a protective mode, limiting or disabling clutch functionality.

• 5085E
• 5090E
• 5090EL
• 5100E
• 5045E
• 5055E
• 5065E
• 5075E
• 5065M
• 5075M
• 5085M
• 5100M
• 5100MH
• 5100ML
• 5115ML
• 5095M
• 5095MH
• 5105M
• 5015ML
• 5090M
• 5115M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 5075GV
• 5090GV
• 5075GN
• 5090GN
• 5105GN
• 5075GF
• 5090GF
• 5105GF
• 5075GL
• 5090GL
• 5100GL
• 6110D
• 6125D

1. 1

   Verify the physical position and alignment of the clutch pedal switch (S72) and the clutch pedal potentiometer (B65) to ensure neither is sticking, loose, or physically misaligned with the pedal linkage.

2. 2

   Use a multimeter to measure the voltage of the clutch pedal potentiometer as you slowly depress and release the pedal (voltage should scale smoothly without dead spots or erratic jumps).

3. 3

   Test the clutch pedal switch for continuity to ensure it correctly opens and closes at the designated points of the pedal's travel.

4. 4

   Inspect the wiring harnesses and connectors linking the switch and potentiometer to the transmission control unit for corrosion, chafing, or disconnected pins.

1. 1

   Adjust Alignment

   If the switch or sensor is physically misaligned but tests fine electrically, adjust their mounting brackets so their actuation matches the physical travel of the clutch pedal.

2. 2

   Replace Faulty Components

   If the potentiometer provides incorrect voltage readings or the switch fails the continuity test, disconnect the battery, unplug the faulty component's harness, unbolt it from the pedal assembly, and install the replacement part.

3. 3

   Repair Wiring

   Repair or replace any damaged wiring or connectors found during the diagnostic phase.

4. 4

   Software/Calibration

   After replacing the potentiometer, you must clear the fault codes. Depending on the tractor model, a clutch pedal calibration procedure (often done via the tractor's CommandCenter display or diagnostic mode) is required to teach the control unit the new sensor's minimum and maximum voltage values.