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U0104 on Hyundai Tucson

Lost Communication with Cruise Control Module

Factory diagnostic protocol and troubleshooting wire for fault code U0104 specifically for the Hyundai Tucson (2021–2026, 2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP)).

Verified OEM Telemetry & Field Repair Tree
Hyundai Tucson2021–2026
Hyundai Tucson
SUV2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP)
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
Tucson SAE Mode $01
ECU Network Bus
500 kbps CAN-FD
ISO 15765-4 Compliant
Drivability Status
Not Recommended
Low urgency level
Est. Repair Cost
$100 - $450 (DIY: $0 - $150)
Parts & Labor DIY
Check U0104 On Another Hyundai Model:
Diagnose U0104 on Specific Tucson Model Year:

1. Symptoms of U0104 on Hyundai Tucson

When the Engine Control Module (ECM/PCM) on your Hyundai Tucson (2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP)) logs fault code U0104, drivers commonly observe:

Adaptive Cruise Control (ACC) disabled on Hyundai Tucson (2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP))
Pre-Collision System warning light on on Hyundai Tucson (2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP))
Check Engine Light on on Hyundai Tucson (2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP))
Hyundai Tucson OBD-II Port Location
The 16-pin diagnostic connector is located Driver footwell directly above brake pedal. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Hyundai Tucson

Historical warranty claims and technical repair bulletins for Hyundai Tucson point to the following failure distribution:

55%
Blocked or dirty front radar sensor in grille/bumper (Hyundai OEM Part)
25%
Blown radar module fuse (Hyundai OEM Part)
12%
Faulty radar cruise control module (Hyundai OEM Part)
8%
Misaligned radar sensor following minor bumper bump (Hyundai OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for Hyundai Tucson.

3. Step-by-Step DIY Repair Guide for Hyundai Tucson

01
Clean Front Radar Sensor in Grille

Clean snow, ice, mud, or dead bugs off front radar emblem. on the Hyundai Tucson equipped with 2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP).

Required Tool: Microfiber Towel
02
Check ACC / Radar Fuse

Verify power feed to radar sensor. on the Hyundai Tucson equipped with 2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP).

Required Tool: Test Light
03
Perform Radar Aiming Calibration

Execute optical/radar alignment procedure if bumper was removed. on the Hyundai Tucson equipped with 2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP).

Required Tool: Calibration Target, Scan Tool
04
Clear Trouble Codes

Clear DTCs and test cruise on highway. on the Hyundai Tucson equipped with 2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP).

Required Tool: OBD-II Scanner
Recommended Parts & Testing Tools

Equipment for Diagnosing Hyundai Tucson (U0104)

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Direct-Fit Replacement Part

Hyundai Tucson OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

Direct-fit replacement assembly engineered to OEM tolerances for Hyundai Tucson.

$45 – $95 Prime
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Sensor Signal Voltage Meter

AstroAI Auto-Ranging Digital Multimeter

4.6 / 5.0 (Best Seller)

Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.

$29.99 Prime
View on Amazon
Top Mobile OBD-II Scanner

BlueDriver Bluetooth Pro OBDII Scan Tool

4.7 / 5.0 (50,000+ Reviews)

Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.

Compare OEM & Aftermarket Replacement Sensors for Hyundai TucsonVerified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
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Other Common Fault Codes on Hyundai Tucson

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Hyundai Tucson:

4. Hyundai Tucson U0104 FAQs

What causes code U0104 to trigger on a Hyundai Tucson?

On the Hyundai Tucson (2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP)), U0104 is most frequently caused by Blocked or dirty front radar sensor in grille/bumper or Blown radar module fuse.

Where is the OBD-II port located on my Hyundai Tucson?

On the Hyundai Tucson, the 16-pin DLC diagnostic connector is located Driver footwell directly above brake pedal. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my Hyundai Tucson with code U0104?

Yes. Normal driving is unaffected, but Adaptive Cruise Control will not engage. Given that U0104 carries a Low severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.