John Deere PTP158.1 – PTP: Vehicle System Recovery Failure

The Power Train Control Unit (PTI) has detected low voltage in the electrical system, specifically a low supply voltage to the transmission control unit. The system logs this fault when it is unable to recover after attempting to return the vehicle to Park and adjusting the electrical load or engine RPM, indicating a persistent charging or voltage supply issue.

• 8245R
• 8270R
• 8295R
• 8320R
• 8345R
• 9230
• 9330
• 9430
• 9530
• 9630
• T560
• T660
• T670
• 944 X

1. 1

   Perform the initial recovery procedure: Return the vehicle to Neutral or Park, reduce the electrical load by turning off non-essential components, and increase engine RPM to encourage alternator output

2. 2

   Conduct a visual inspection of the charging system, checking the batteries and alternator for damage, corrosion, or accumulated debris

3. 3

   Inspect relevant system fuses, specifically checking fuse F24 (exact fuse location may vary by machine model)

4. 4

   Test the batteries to ensure they are holding a proper charge

5. 5

   Test the alternator's output to confirm it is charging correctly under load

1. 1

   Perform diagnostic checks

   Perform the diagnostic checks listed above.

2. 2

   Replace charging components

   If a faulty battery, alternator, or fuse is identified, replace the component.

3. 3

   Test wiring harness

   If the charging system components are functional, a technician would then test the PTP controller's wiring harness for continuity, shorts, and high resistance.

4. 4

   Replace PTP control unit

   If the wiring harness is in good condition, the final step would be to test and likely replace the PTP control unit itself.

5. 5

   Calibrate transmission

   After replacement of a component, a transmission calibration may be necessary.