U0140 — Lost Communication With Body Control Module
Category: Network / Communication Severity: Medium
Updated:
DTC code U0140 means: Lost Communication With Body Control Module. It falls under the "Network / Communication" category, with an estimated severity of Medium. Common causes include failed BCM or power supply fault, blown BCM fuse and water in the BCM; it's worth confirming the diagnosis before replacing parts.
Possible causes
- Failed BCM or power supply fault
- Blown BCM fuse
- Water in the BCM
- Damaged CAN wiring
Symptoms
- Lights, wipers or central locking not working
- Warning lights on
- Battery draining
How to diagnose it step by step
- Check BCM fuses.
- Check power and grounds.
- Look for moisture in the module.
- Measure the CAN bus.
- Replace and program the BCM.
How to fix it
Check BCM fuses and grounds, and look for water ingress (windshield seal, drains). If the BCM is damaged, replace and program it.
Estimated repair cost
New BCM with programming: $400–1,200.
Frequently asked questions
What does DTC code U0140 mean?
Lost Communication With Body Control Module.
Is code U0140 serious?
Severity Medium. Not urgent, but worth diagnosing to avoid bigger damage.
Can I keep driving with code U0140?
Only if the lights and wipers work.
Related codes
U0151 U0155 U0121 U0164 U0101 U0100
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