ACU 524018.31 – Delayed RHR Neutral/Park Transition

ACU 524018.31 (ACU )

Code: 524018.31



This error code, ACU 524018.31, is triggered when the transition time from neutral to park position by the Reversible Handle Reverser (RHR) lever takes longer than expected. This extended transition can disrupt normal operational sequencing and suggests a potential malfunction in the lever mechanism or control system.


As a precautionary measure to avoid unintended movements and maintain safety, the control unit commands the machinery into PARK mode, though this position is recoverable once the issue is addressed.


  • Inspect the RHR lever and associated linkage for any mechanical resistance or obstructions that could be causing the delayed transition between neutral and park.
  • Check for wear or damage on the lever itself or within the control mechanism that could impede smooth operation.
  • Ensure that all moving parts in the linkage are well-lubricated and free of debris that might hinder motion.
  • Utilize diagnostic tools to monitor the response times and operational parameters of the RHR system to better understand the source of the delay.
  • Adjust or recalibrate the RHR settings as per the manufacturer’s guidelines to ensure optimal performance and response times.
  • If mechanical adjustments do not resolve the issue, further investigation into the electronic control system may be necessary, potentially involving software updates or component replacements.


Proper function of the RHR lever is crucial for safe operation, especially during transitions between operating modes. Regular maintenance and prompt attention to any operational delays are vital to preventing potential hazards and ensuring the reliability of the transmission system.