U0073 — Control Module Communication Bus A Off
Category: Network / Communication Severity: High
Updated:
DTC code U0073 means: Control Module Communication Bus A Off. It falls under the "Network / Communication" category, with an estimated severity of High. Common causes include short on the CAN bus, faulty module and loose or corroded connector; it's worth confirming the diagnosis before replacing parts.
Possible causes
- Short on the CAN bus
- Faulty module
- Loose or corroded connector
- Low battery or bad ground
Symptoms
- Several warning lights
- Loss of electronic functions
- Possible no-start
How to diagnose it step by step
- Check battery and grounds.
- Read codes from all modules.
- Measure the CAN bus.
- Locate the faulty module or section.
How to fix it
The module has stopped communicating on bus A. Check the battery and grounds, then the CAN wiring and module connectors.
Estimated repair cost
$60–1,500.
Frequently asked questions
What does DTC code U0073 mean?
Control Module Communication Bus A Off.
Is code U0073 serious?
Severity High. Have it checked as soon as possible, especially if it affects safety or the catalytic converter.
Can I keep driving with code U0073?
Not recommended.
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