OBD Guide

U0630

Lost Communication With Engine Coolant Temperature Sensor 4

U0630 is an OBD-II diagnostic trouble code meaning: Lost Communication With Engine Coolant Temperature Sensor 4. Common causes: open or short circuit in the sensor circuit, oxidized or damaged connector pins. Estimated repair cost: $9–39.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$9–39 (est.)

Symptoms

  • Check Engine Light Is On
  • Incorrect temperature readings on the dashboard
  • Increased fuel consumption
  • Problems with engine warming up
  • Reduced engine power

Causes

  • Open or short circuit in the sensor circuit
  • Oxidized or damaged connector pins
  • Malfunction of coolant temperature sensor No. 4
  • Wiring Harness Problems
  • Engine control unit malfunction

How to Fix

  1. Check the integrity of the sensor circuit
  2. Inspect and clean the connector contacts
  3. Test sensor resistance
  4. Replace temperature sensor if necessary
  5. Check connections to the control unit

Related codes

Error U0630 by Vehicle Brand

FAQ

What does the U0630 code mean?

U0630 is an OBD-II diagnostic trouble code that indicates: Lost Communication With Engine Coolant Temperature Sensor 4

What causes a U0630 error code?

The most common causes of U0630 include: Open or short circuit in the sensor circuit; Oxidized or damaged connector pins; Malfunction of coolant temperature sensor No. 4; Wiring Harness Problems.

How do I fix a U0630 diagnostic trouble code?

To fix U0630: Check the integrity of the sensor circuit. Inspect and clean the connector contacts. Test sensor resistance. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U0630?

Yes, but get it checked soon

How much does it cost to fix U0630?

The estimated repair cost for U0630 is $9–39. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat