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U0104 on Toyota Grand Highlander

Lost Communication with Cruise Control Module

Factory diagnostic protocol and troubleshooting wire for fault code U0104 specifically for the Toyota Grand Highlander (2024–2026, 2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD).

Verified OEM Telemetry & Field Repair Tree
Toyota Grand Highlander2024–2026
Toyota Grand Highlander
SUV2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
Grand Highlander 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 Toyota Model:
Diagnose U0104 on Specific Grand Highlander Model Year:

1. Symptoms of U0104 on Toyota Grand Highlander

When the Engine Control Module (ECM/PCM) on your Toyota Grand Highlander (2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD) logs fault code U0104, drivers commonly observe:

Adaptive Cruise Control (ACC) disabled on Toyota Grand Highlander (2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD)
Pre-Collision System warning light on on Toyota Grand Highlander (2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD)
Check Engine Light on on Toyota Grand Highlander (2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD)
Toyota Grand Highlander OBD-II Port Location
The 16-pin diagnostic connector is located Driver side lower knee panel above dead pedal. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Toyota Grand Highlander

Historical warranty claims and technical repair bulletins for Toyota Grand Highlander point to the following failure distribution:

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

3. Step-by-Step DIY Repair Guide for Toyota Grand Highlander

01
Clean Front Radar Sensor in Grille

Clean snow, ice, mud, or dead bugs off front radar emblem. on the Toyota Grand Highlander equipped with 2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD.

Required Tool: Microfiber Towel
02
Check ACC / Radar Fuse

Verify power feed to radar sensor. on the Toyota Grand Highlander equipped with 2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD.

Required Tool: Test Light
03
Perform Radar Aiming Calibration

Execute optical/radar alignment procedure if bumper was removed. on the Toyota Grand Highlander equipped with 2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD.

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

Clear DTCs and test cruise on highway. on the Toyota Grand Highlander equipped with 2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD.

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

Equipment for Diagnosing Toyota Grand Highlander (U0104)

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Direct-Fit Replacement Part

Toyota Grand Highlander OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

Direct-fit replacement assembly engineered to OEM tolerances for Toyota Grand Highlander.

$45 – $95 Prime
Check Fitment on Amazon
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 Toyota Grand HighlanderVerified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
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Other Common Fault Codes on Toyota Grand Highlander

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Toyota Grand Highlander:

4. Toyota Grand Highlander U0104 FAQs

What causes code U0104 to trigger on a Toyota Grand Highlander?

On the Toyota Grand Highlander (2.4L Turbo / 2.5L Hybrid / Hybrid MAX 362HP Turbo AWD), 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 Toyota Grand Highlander?

On the Toyota Grand Highlander, the 16-pin DLC diagnostic connector is located Driver side lower knee panel above dead 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 Toyota Grand Highlander 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.