OBD Guide

P0939

Hydraulic Oil Temperature Sensor Circuit Low

P0939 is an OBD-II diagnostic trouble code meaning: Hydraulic Oil Temperature Sensor Circuit Low. Common causes: hydraulic oil temperature sensor malfunction, open or short circuit in the sensor circuit. Estimated repair cost: $17–56.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$17–56 (est.)

Symptoms

  • Incorrect operation of the automatic transmission
  • Increased noise during power steering operation
  • Check Engine Light Illuminates
  • Reduced hydraulic system efficiency

Causes

  • Hydraulic oil temperature sensor malfunction
  • Open or short circuit in the sensor circuit
  • Poor contact in wiring connectors
  • Problems with the engine control unit
  • Contaminated or low hydraulic oil level

How to Fix

  1. Check the level and condition of the hydraulic oil
  2. Inspect the sensor circuit for damage
  3. Check sensor connectors and contacts
  4. Test hydraulic oil temperature sensor
  5. Replace sensor if necessary

Related codes

Error P0939 by Vehicle Brand

FAQ

What does the P0939 code mean?

P0939 is an OBD-II diagnostic trouble code that indicates: Hydraulic Oil Temperature Sensor Circuit Low

What causes a P0939 error code?

The most common causes of P0939 include: Hydraulic oil temperature sensor malfunction; Open or short circuit in the sensor circuit; Poor contact in wiring connectors; Problems with the engine control unit.

How do I fix a P0939 diagnostic trouble code?

To fix P0939: Check the level and condition of the hydraulic oil. Inspect the sensor circuit for damage. Check sensor connectors and contacts. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P0939?

Yes, but get it checked soon

How much does it cost to fix P0939?

The estimated repair cost for P0939 is $17–56. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat