Invalid Data Received From ECM/PCM "B"
The U0442 code means the vehicle's onboard diagnostic system has detected: Invalid Data Received From ECM/PCM "B". This is a moderate severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- moderate
- Estimated cost
- $50 - $500 (usually the fault behind the bad data, not the network itself)
Network codes mean modules are not communicating. You need a scanner that reads all systems to find the problem.
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What Are the Symptoms of U0442?
- Check Engine or related warning light on
- Functions relying on data from the ECM/PCM "B" may act erratically
- Often intermittent
What Causes U0442? (Most Likely First)
- The ECM/PCM "B" is transmitting, but its data is implausible - often a failing sensor feeding it High
- Intermittent wiring fault corrupting messages Moderate
- Software mismatch after service Moderate
- Failing ECM/PCM "B" Low
Can I Still Drive with U0442?
Yes, but fix soon. U0442 is rated moderate severity. It is not an immediate stop-driving fault, but it will not clear itself — book the repair rather than ignoring the light.
Frequently Asked Questions
What does U0442 mean?
U0442 means this module IS communicating with the ECM/PCM "B", but the data it sends fails plausibility checks. Diagnose the source module first.
Can I keep driving with U0442?
Usually yes for a short period. The affected function may be degraded, and intermittent wiring faults tend to worsen - diagnose soon.
Should I replace the module for U0442?
Not first. Most communication codes are power, ground, fuse, or wiring problems. Replace the module only after those test good - modules are expensive and often require programming.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose U0442?
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Scan the ECM/PCM "B" itself - the invalid data usually traces to a fault code stored there.
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Fix any codes in the source module first; this code often clears with them.
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Check for recent programming or battery-disconnect events.
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If the source module is clean, monitor the specific data value flagged and follow the OEM pinpoint test.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
Which Vehicles Commonly Get U0442?
- All OBD-II vehicles - network (U) codes are standardized across makes
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