U046E

Code

Generic U — Network/User

Invalid Data Received From Exhaust Gas Sensor Module B

Brand: Generic

Type: U — Network/User

Views: UK: 28 EN: 30 RU: 34

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Page language: EN

MIL (Check Engine) or warning indicator illuminated
Reduced performance, limp-home mode, or emission-related limp strategies
Missing or implausible exhaust sensor data on a scan tool (e.g., NaN, 0, max value)
Stored U046E and possibly other network/communication U-codes
Possible failed emissions test or incorrect catalyst/regeneration behavior

Read all stored and pending DTCs from all modules; record freeze frame and live data
Check for related network codes (U0100, U0155, U0415, etc.)
Verify battery voltage (should be within normal operating range during checks)
Visually inspect connectors and harness for corrosion, damage, or disconnection at Exhaust Gas Sensor Module B and related junctions
Use a scan tool to view live data from Exhaust Gas Sensor Module B and verify update rate/values
Check CAN/LIN bus physical layer: measure bus voltages and look for dominant/recessive levels and continuity to other modules

CAN/LIN message ID assigned to Exhaust Gas Sensor Module B (manufacturer-specific)
Expected message frequency (typical module alive message every 50–500 ms)
Data payload: sensor readings (exhaust gas concentration / temperature / sensor status) — values should be within physical ranges and not contain invalid flags
Checksum/CRC or sequence counters if used by the module to validate packets
Signal voltage levels: CANH/CANL differential behavior (dominant vs recessive) and bus termination presence

Confirm DTC: Clear codes and attempt to reproduce. Note whether code returns immediately or intermittently.
Scan bus data: Using a capable scan tool, monitor Exhaust Gas Sensor Module B live data and message rate. Look for stale, repeating, invalid, or out-of-range values.
Compare modules: Check the same parameters from Exhaust Gas Sensor Module A (if present) or other related modules to verify network-wide vs module-specific issue.
Visual and power checks: With ignition off, disconnect the module connector and inspect pins for corrosion, bent pins, or water intrusion. With ignition on, verify module supply voltage and ground at the connector.
Bus physical layer: Measure CANH/CANL voltages (key off and key on). With the bus active, verify proper idle voltages and that dominant/recessive states toggle when data is present. Check termination resistances.
Wiggle test: With a data logger or scan tool monitoring, gently wiggle wiring near harnesses and connectors while observing for code set or data corruption to find intermittent faults.
Substitute or reflash: If wiring and power/ground are good, check for available module software updates or recall bulletins. If still unresolved, consider replacing or bench-testing the exhaust gas sensor module B per manufacturer procedures.
Re-test: After repair or replacement, clear codes and verify that valid messages are received consistently and related drivability/emissions behavior is normal.