U2142

Code

OPEL U — Network/User

CAN-Bus No Communication with YRS (Yaw Rate Sensor)

Brand: OPEL

Type: U — Network/User

Views: UK: 5 EN: 8 RU: 7

AI status

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Page language: EN

Causes

Open or shorted CAN wiring (CAN_H/CAN_L) between YRS and network
Faulty or unpowered Yaw Rate Sensor (YRS)
Corroded, loose or damaged connector at YRS or gateway module
Lost or faulty gateway/ABS/ESP control module that forwards YRS messages
Incorrect termination or missing CAN bus resistor(s)
Software/configuration mismatch after module replacement or update

Symptoms

MIL/ABS/ESP lights illuminated; stability control disabled message
Loss of yaw/rotation input to ESP/ABS systems, causing degraded handling control
One or more communication DTCs present for ABS/ESP or gateway modules
Possible limp-home behavior or inhibited driver aids (traction control, lane assist)
No YRS data visible on a network scan tool

What to check

Read and record all stored DTCs and freeze-frame data with a capable scanner
Check for additional CAN or module communication errors (other U-codes) to determine scope
Attempt to communicate with YRS via diagnostic tool (if supported) — note success/failure
Visually inspect YRS connector and wiring harness for damage, corrosion, bent pins, or water ingress
Check power and ground at the YRS (battery voltage and good chassis ground)
Measure CAN_H and CAN_L voltages with ignition ON and engine running if required (see signal parameters)

Signal parameters

CAN bus idle (recessive): CAN_H ≈ 2.5 V, CAN_L ≈ 2.5 V (differential ≈ 0 V)
CAN bus dominant: CAN_H ≈ 3.5 V, CAN_L ≈ 1.5 V (differential ≈ 2 V)
Typical bus bit rates used on vehicle networks: 500 kb/s or 250 kb/s (verify for the specific Opel model)
Expected: regular CAN frames containing YRS data at a repeating rate when vehicle systems are active (frequency depends on vehicle, often 10–100 Hz)
Termination: ~60 ohm between CAN_H and CAN_L at the two ends of the network (combined)

Diagnostic algorithm

Verify DTC: Use a diagnostic scanner to confirm U2142 and note any accompanying codes. Record freeze-frame data.
Check other modules: Scan ABS/ESP, gateway, BCM and engine modules for related communication errors to identify whether fault is isolated to YRS or affects the whole bus.
Visual inspection: Locate the YRS and inspect harness, connector, and mounting for damage, corrosion or water; repair any visible faults.
Power/ground: With key on, measure battery voltage at the YRS power terminal and check a reliable ground. Repair poor power/ground before further testing.
CAN passive checks: With ignition ON, measure CAN_H and CAN_L voltages at the YRS connector (see signal_params). Verify approx. 2.5 V recessive and ~2 V differential when active.
Resistance/continuity: With battery disconnected, check continuity of CAN_H and CAN_L back to ABS/gateway and measure resistance across H–L for proper termination (~60 ohm).
Active bus check: Use oscilloscope or CAN analyzer while cranking/running to verify valid frames and that the YRS transmits messages. Look for repeated errors, bus-off, or dominant stuck states.
Isolate wiring: If bus signals are abnormal, disconnect the YRS connector and re-check bus. If bus returns to normal, suspect YRS short or internal failure. If not, trace harness to next node.
Module swap/test: If wiring and power/ground are good but no communication, replace or bench-test the YRS per manufacturer procedures; if still no communication and other nodes missing the messages, suspect gateway/ESP module failure.
Clear codes and test drive: After repair, clear DTCs and perform verification drive; confirm codes do not return and YRS data is present and plausible.
Safety note: When probing alive CAN wires use appropriate back-probing tools; avoid shorting CAN_H to CAN_L or to supply/ground.

Likely causes

Damaged connector or wiring at the YRS (water ingress, broken pins)
Failed Yaw Rate Sensor (internal electronics)
Faulty ESP/ABS module or CAN gateway not transmitting/receiving YRS messages
Short to battery or ground on CAN lines causing bus to be unreadable

Fault status

⚠️ Status

No communication received from Yaw Rate Sensor (YRS) on CAN bus — messages missing or bus errors detected.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1-3 hours

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