U0119 Code: Meaning, Symptoms, Causes & Fix

Overview

Symptoms

• hesitation under acceleration
• reduced fuel economy
• hard starting

Common causes

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

How to diagnose U0119

1. Confirm U0119 and capture freeze-frame data with a professional scan tool.
2. Inspect wiring, connectors, and grounds related to lost communication with fuel cell control module for obvious defects.
3. Check CAN high/low integrity, network termination resistance, and module wake-up status.
4. Check for related DTCs to identify the root-cause chain before replacing parts.
5. After repair, clear codes and confirm readiness monitors complete without recurrence.

Severity of code U0119

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

Can you drive with U0119?

Most vehicles can be driven short-term with U0119, 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)

1. Repair obvious wiring/connector faults first to prevent repeat parts replacement.
2. Address the root fault mode (communication) in the lost communication with fuel cell control module circuit/system.
3. Apply the required relearn/adaptation procedure if specified by service information.
4. Road-test and verify U0119 remains cleared under the conditions that originally set the code.

Fix options

• Stabilize voltage supply and module grounds.
• Scan all modules for communication chain faults.
• Clear DTCs and verify with live data and completed drive cycle.

Typical repair cost

$220-$1100

Common mistakes when diagnosing U0119

• 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.

U0119 in common vehicles

U0119 appears across makes such as Ford, Toyota, Honda, Chevrolet. Failure patterns differ by platform: wiring routes, software calibration, and component supplier revisions can change root cause.

Frequently asked questions

What causes U0119?

U0119 is commonly set by communication faults affecting lost communication with fuel cell control module.

How much does it cost to fix U0119?

For U0119, repair costs are typically $220-$1100 depending on exact root cause, labor rates, and part quality.

Can I clear U0119 without repair?

You can clear U0119 temporarily, but the code usually returns until the underlying fault is corrected.

Helpful tools

• Estimate repair cost
• Decode your VIN
• Calculate fuel cost