B14C4

Code

Generic B — Body

Occupant Classification Sensor Circuit — High Input

Brand: Generic

Type: B — Body

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Open or shorted wiring in the OCS harness (short to battery voltage)
Faulty occupant classification sensor or sensor mat
Corroded or loose connector at the sensor or SRS module
Faulty SRS/airbag control module input circuit
Incorrect repair or aftermarket seat/heating elements interfering with the sensor
Intermittent contact caused by seat movement or damaged insulation

Observe and follow SRS safety procedure: disable battery negative and wait manufacturer-specified time before working on seat/SRS components.
Use a scan tool to read live OCS sensor data and confirm B14C4 is active; note freeze-frame conditions.
Visually inspect seat connectors, harness routing, and sensor mat for damage, water ingress, or corrosion.
Backprobe the sensor connector with harness connected and key ON (follow safety guidance) and measure signal voltage relative to ground.
Check reference supply (typically 5V or ignition reference) and ground at the sensor connector.
Perform wiggle test on harness and connector while monitoring live data to find intermittent faults.

Reference supply commonly ~5 V (verify factory specification); expected signal typically within ~0.5–4.5 V range under normal conditions.
"High input" generally means sensor signal is above the allowed maximum threshold (often >4.8–5.5 V) or reads as over-voltage.
Open-circuit or short-to-B+ can drive the signal toward battery voltage (~12 V) or a value above the ECU input threshold.
Expected circuit continuity: low ohms between sensor ground and chassis ground; signal wire should not be shorted to battery positive.

Safety: Disable vehicle battery negative and wait the manufacturer-recommended time to disable SRS before accessing the seat or connectors.
Clear the code, then reconnect battery and use a scan tool to reproduce and confirm B14C4; record live data and freeze-frame.
With key ON (engine off) and harness connected, backprobe the OCS connector: verify reference voltage (typically 5 V) and ground presence.
Measure the sensor signal voltage at the connector. If signal is above specified maximum, check for short to battery (measure voltage between signal wire and battery +).
If sensor supply and ground are okay but signal is high, disconnect the sensor and measure voltage on the harness signal pin: if high remains, fault in wiring or ECU; if it returns to normal, suspect sensor.
Inspect wiring for pin damage, water intrusion, or chafing where it could contact battery power. Repair any damaged sections and replace corroded connectors.
Check continuity/resistance from sensor signal to SRS module pin with battery disconnected to locate opens or unexpected shorts.
If wiring and connectors test good, replace the occupant classification sensor/mat assembly and retest.
If problem persists after sensor and wiring replacement, test or replace the SRS/airbag control module per manufacturer procedures.
After repairs, clear codes, perform required system initialization/calibration for OCS (if applicable), and verify no return of the code.