OBD Guide

U1186

Lost Communication With Adaptive Cruise Control Module

U1186 is an OBD-II diagnostic trouble code meaning: Lost Communication With Adaptive Cruise Control Module. Common causes: broken or damaged wires in the communication circuit, poor contact in acc module connectors. Estimated repair cost: $167–500.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$167–500 (est.)

Symptoms

  • Adaptive cruise control does not work
  • Check Engine light comes on
  • Error message on the instrument panel display
  • Disabling the security system (on some models)

Causes

  • Broken or damaged wires in the communication circuit
  • Poor contact in ACC module connectors
  • Malfunction of the adaptive cruise control module
  • ACC module power problems
  • CAN bus fault

How to Fix

  1. Check ACC module fuses
  2. Inspect and check module connectors and wiring
  3. Check ACC module supply voltage
  4. Carry out CAN bus diagnostics
  5. Replace ACC module if necessary

Related codes

FAQ

What does the U1186 code mean?

U1186 is an OBD-II diagnostic trouble code that indicates: Lost Communication With Adaptive Cruise Control Module

What causes a U1186 error code?

The most common causes of U1186 include: Broken or damaged wires in the communication circuit; Poor contact in ACC module connectors; Malfunction of the adaptive cruise control module; ACC module power problems.

How do I fix a U1186 diagnostic trouble code?

To fix U1186: Check ACC module fuses. Inspect and check module connectors and wiring. Check ACC module supply voltage. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U1186?

Yes, but get it checked soon

How much does it cost to fix U1186?

The estimated repair cost for U1186 is $167–500. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat