Lost Communication With Ride Quality Control Module
What does U0139 mean?
The U0139 code means the vehicle's onboard diagnostic system has detected: Lost Communication With Ride Quality Control Module. This is a low severity code.
Common Symptoms
- Ride quality mode selection not working
- Comfort/Sport/Normal ride modes unavailable
- Suspension warning message on dashboard
- Ride quality feels different than normal
- Drive mode selector not responding for suspension changes
Probable Causes (Ranked by Likelihood)
- Failed ride quality control module Very High
- Damaged wiring to ride quality module High
- Drive mode selector switch fault Moderate
- Corroded connector at ride quality module Moderate
- Module software corruption Low
Step-by-Step Diagnostic Procedure
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Scan for DTCs in the suspension and body modules
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Check CAN bus wiring and connector at the ride quality module
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Verify power supply and ground at the module
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Test the drive mode selector switch for proper operation
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Check for available software updates for the module
Frequently Asked Questions
Can I drive with code U0139?
Yes. The vehicle will default to a standard ride setting. You will lose the ability to switch between comfort, sport, and other ride modes, but the vehicle is safe to drive.
What causes U0139?
A failed ride quality control module or damaged wiring are the most common causes. This module controls the selectable ride modes found on luxury vehicles.
Is this the same as a bad shock absorber?
No. U0139 is a communication issue with the module that controls ride modes. The physical shock absorbers may be fine. However, they will default to a fixed setting instead of adjusting dynamically.