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DTC codes / C00xx · Brakes, steering and suspension / C0093

C00934WD/AWD Power Transfer Unit Temperature Sensor

C0093 indicates that the all-wheel-drive (AWD) or four-wheel-drive (4WD) control module has detected an abnormal signal from the power transfer unit (PTU) temperature sensor, which monitors the fluid or component temperature inside the transfer case. The computer sets this code when the sensor voltage or resistance falls outside the expected range for the current operating conditions, often due to a faulty sensor, wiring issue, or low fluid level.

SystemChassis
Code typeGeneric (all makes)
SeverityMedium
Fix difficultyIntermediate
AreaBrakes, steering and suspension

Symptoms you may notice

  • Illumination of the AWD or 4WD warning light on the dashboard
  • The vehicle may default to front-wheel drive only, reducing traction
  • Intermittent or permanent loss of all-wheel-drive engagement
  • A message on the driver information center indicating AWD system fault or service required
  • Often no other symptoms besides the warning light, especially in early stages
  • In rare cases, the transfer case may enter a protective mode that limits vehicle speed

Common causes, most likely first

  1. Faulty power transfer unit temperature sensor
  2. Damaged or corroded wiring harness or connector at the sensor
  3. Low or degraded fluid in the power transfer unit causing overheating
  4. Failed sensor signal circuit (open or short) to the control module
  5. Internal mechanical wear in the transfer case affecting sensor readings
  6. Corrosion or water intrusion into the sensor or connector
  7. Software glitch in the AWD control module requiring recalibration or update

How to diagnose and fix it

  1. Scan all modules for related codes and record freeze-frame data to understand when the fault occurs
  2. Inspect the sensor wiring and connector for damage, corrosion, or loose pins; repair as needed
  3. Check the power transfer unit fluid level and condition; top off or replace fluid if contaminated
  4. Test the temperature sensor resistance with a multimeter and compare to manufacturer specifications
  5. If the sensor is faulty, replace it and clear the code; verify the signal returns to normal
  6. Check for technical service bulletins (TSBs) or software updates for the AWD control module
  7. Perform a road test to confirm the AWD system engages properly and the code does not return

Before you replace the transfer case sensor

  • A low fluid level in the power transfer unit is a common cause of this code that is often overlooked because the leak may be slow and not leave visible spots.
  • The sensor itself may be fine; the code can be triggered by a poor ground connection or a chafed wire that only shorts when the vehicle is moving or warm.
  • Some vehicles use the same sensor for both temperature and fluid level, so a code for temperature may actually indicate a level issue.
  • After replacing the sensor, the AWD control module may require a relearn or calibration procedure to prevent the code from returning.
  • Driving with this code may cause the AWD system to disable, which can affect handling in slippery conditions, but it rarely causes immediate mechanical damage.

Can I keep driving with C0093?

You can generally drive with this code, but be aware that the all-wheel-drive system may be disabled, reducing traction in rain, snow, or off-road conditions. Avoid heavy acceleration or towing until the fault is repaired, and have the vehicle inspected soon to prevent potential transfer case damage from low fluid or overheating.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

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