U0284Network Communication

Lost Communication With Body Control Module B

U0284 means a module lost communication with a second body control module (BCM B). This can affect various body electrical functions handled by that module.

🚗 Depends on affected functions. Some body electrical features may not work.
MEDIUM
severity
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🎯 Top Causes, Ranked by Likelihood

#1Wiring or connector fault to the module$50-$300
35%
Open or shorted wiring interrupts communication with BCM B.
#2Failed body control module B$200-$800
30%
An internal failure stops the module from communicating.
#3Poor power or ground to the module$50-$250
20%
Missing power or ground keeps the module offline.
#4Bus fault affecting the module$100-$500
15%
A network problem can drop the module off the bus.

🩺 Common Symptoms

💰 Repair Cost: DIY vs Shop

DIY Cost
$50-$300
Shop Cost
$150-$800

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🔧 How to Diagnose U0284

1Scan modules and confirm which are communicating
2Verify power and ground at BCM B
3Inspect wiring and connectors to the module
4Test the bus signal reaching the module

❓ Frequently Asked Questions

Can I drive with U0284?
It depends on what functions BCM B controls. Some body features may not work. Get it diagnosed.
What is body control module B?
It is a secondary body control module that manages certain body electrical functions on some vehicles.
What causes U0284?
Wiring or connector faults, a failed module, or a power and ground problem.

🔗 Related Codes

U0140U0155U0121U0164
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