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U0104 on BMW: Symptoms, Causes & Fix

Lost Communication with Cruise Control Module

Official technical diagnostic wire for fault code U0104 specifically affecting BMW vehicles (3 Series, 5 Series, 7 Series, X3, X5).

Sensor Voltage Ref
0.1V – 5.0V Ref
BMW Factory Standard
CAN Bus Speed
500 kbps CAN-FD
ISO 15765-4 Diagnostic Bus
Drivability Status
Not Recommended
Low urgency level
Est. Repair Cost
$100 - $450 (DIY: $0 - $150)
Parts & Labor DIY
Model-Specific Diagnostic Wires

Select Your BMW Model for U0104:

9 Models Available

1. Common Symptoms on BMW Vehicles

When BMW Engine Control Modules (ECM) trigger fault code U0104, drivers typically report:

Adaptive Cruise Control (ACC) disabled on BMW Powertrains
Pre-Collision System warning light on on BMW Powertrains
Check Engine Light on on BMW Powertrains

2. Root Causes on BMW Engines

Historical diagnostic claims across BMW engines point to the following failure distribution:

55%
Blocked or dirty front radar sensor in grille/bumper (BMW OEM Part)
25%
Blown radar module fuse (BMW OEM Part)
12%
Faulty radar cruise control module (BMW OEM Part)
8%
Misaligned radar sensor following minor bumper bump (BMW OEM Part)

3. Step-by-Step Fix Protocol for BMW

01
Clean Front Radar Sensor in Grille

Clean snow, ice, mud, or dead bugs off front radar emblem. on BMW engines.

Required Tool: Microfiber Towel
02
Check ACC / Radar Fuse

Verify power feed to radar sensor. on BMW engines.

Required Tool: Test Light
03
Perform Radar Aiming Calibration

Execute optical/radar alignment procedure if bumper was removed. on BMW engines.

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

Clear DTCs and test cruise on highway. on BMW engines.

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

Equipment for Diagnosing BMW (U0104)

Prime Fast Delivery & Verified Fitment
Direct-Fit Replacement Part

BMW OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

Direct-fit replacement assembly engineered to OEM tolerances for BMW.

$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.

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4. BMW U0104 Frequently Asked Questions

What does code U0104 mean on a BMW?

On BMW vehicles, U0104 indicates that the Engine Control Module (ECM) detected lost communication with cruise control module. This typically points to Blocked or dirty front radar sensor in grille/bumper or Blown radar module fuse.

Can I continue driving my BMW with code U0104?

Yes. Normal driving is unaffected, but Adaptive Cruise Control will not engage. Because this code carries a Low severity rating on BMW powertrains, we recommend scanning live data values promptly to prevent secondary damage.

How much does it cost to fix code U0104 on a BMW?

Estimated DIY parts cost ranges from $100 - $450 (DIY: $0 - $150), while professional shop repairs at an authorized BMW dealership or independent specialist typically range from $180 to $380 including diagnostic labor.