Severity Low
U0286

Radiator Tamper Device Communication Lost

📅 Last reviewed: July 2026
What does the U0286 code mean?

Diagnostic trouble code U0286 indicates that the main control module (PCM, BCM, or gateway) has stopped receiving valid data messages over the serial communication bus (CAN or LIN) from the radiator tamper device module. According to SAE J2012 network architecture for U0xxx codes, the absence of expected periodic traffic from the subordinate node triggers a communication failure indicator, preventing the main controller from monitoring the radiator's safety status. This is purely a network condition and does not imply mechanical damage to the radiator, though it may coexist with widespread electrical faults in the vehicle.

Low
Severity
Variable
Typical Cost
Low
Frequency

1. Commonly Affected Makes

This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.

2. Most Common Causes

3. Symptoms You Will Notice

4. Step-by-Step Diagnosis

1

Scan for all stored codes and freeze frame data

2

Inspect the communication bus wiring and connectors for damage, corrosion, or loose connections

3

Check power and ground circuits at the radiator tamper device module

4

Test the module's communication signals with an oscilloscope or scan tool

5

If all else is normal, replace the radiator tamper device module or the main control module as needed

5. Frequently Asked Questions

Is it safe to drive?

Yes, it is generally safe to drive with this code as it is low severity and does not affect engine or transmission operation. However, the radiator tamper detection feature may be disabled, so have it diagnosed soon.

How much does it cost to fix?

Repair costs typically range from $100 to $400, depending on whether the issue is a wiring repair, connector replacement, or module replacement.

6. Related Codes

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