U0164 Code: Meaning, Symptoms, Causes & Fix

Overview

Code U0164 indicates a fault in Lost Communication With HVAC Control Module, typically within module-to-module CAN communication.

Symptoms

module not responding in scan tool
intermittent no-start or limp mode
multiple warning lights at once

Common causes

Network termination or gateway fault affecting lost communication with hvac control module
Module power/ground instability
Connector pin damage/corrosion or harness stress near related components

How to diagnose U0164

Confirm U0164 and capture freeze-frame data with a professional scan tool.
Inspect wiring, connectors, and grounds related to lost communication with hvac control module for obvious defects.
Check CAN high/low integrity, network termination resistance, and module wake-up status.
Check for related DTCs to identify the root-cause chain before replacing parts.
After repair, clear codes and confirm readiness monitors complete without recurrence.

Severity of code U0164

Moderate: This code is moderate severity: the vehicle may still operate, but fault progression can increase repair cost over time.

Can you drive with U0164?

Most vehicles can be driven short-term with U0164, but postpone heavy load/highway driving until repaired.

If the warning lamp is flashing or drivability/safety is affected, avoid driving and diagnose immediately.

How to fix it (step-by-step)

Repair obvious wiring/connector faults first to prevent repeat parts replacement.
Address the root fault mode (communication) in the lost communication with hvac control module circuit/system.
Apply the required relearn/adaptation procedure if specified by service information.
Road-test and verify U0164 remains cleared under the conditions that originally set the code.

Fix options

Repair CAN high/low wiring or termination issue.
Scan all modules for communication chain faults.
Clear DTCs and verify with live data and completed drive cycle.

Typical repair cost

$260-$1300

Common mistakes when diagnosing U0164

Replacing parts without verifying voltage, ground, and signal integrity first.
Ignoring related stored/pending codes that indicate upstream faults.
Skipping post-repair verification drive cycle and readiness checks.

U0164 in common vehicles

U0164 appears across makes such as Nissan, Hyundai, Kia, Volkswagen. Failure patterns differ by platform: wiring routes, software calibration, and component supplier revisions can change root cause.

Frequently asked questions

What causes U0164?

U0164 is commonly set by communication faults affecting lost communication with hvac control module.

How much does it cost to fix U0164?

For U0164, repair costs are typically $260-$1300 depending on exact root cause, labor rates, and part quality.

Can I clear U0164 without repair?

You can clear U0164 temporarily, but the code usually returns until the underlying fault is corrected.