4-Pin Oxygen Sensor (O2) Connector – OEM 1928404993 | 2.8mm & 3.5mm Female

The OEM 1928404993 is a 4-pin female connector used in oxygen (O2) sensor and air-fuel ratio (AFR) sensor harnesses across multiple automotive brands. Available in 2.8mm and 3.5mm terminal pitch variants, bare or with 15cm pre-wired leads. Replacing a degraded O2 sensor connector restores clean sensor signal continuity and eliminates P0130–P0167 oxygen sensor fault codes.

Key Specifications

O2 Sensor Connector Pin Functions

A standard 4-pin O2 sensor connector serves: heater power (+12V), heater ground, sensor signal, and sensor ground. The heater circuit (pins 1–2) brings the sensor to operating temperature quickly; the signal circuit (pins 3–4) transmits the lambda voltage to the ECU. A corroded connector on either circuit causes heater faults (P0030, P0036) or signal faults (P0130–P0167).

Why O2 Sensor Connectors Fail

Oxygen sensor connectors are mounted in the exhaust system environment, exposed to extreme heat, road spray, and vibration. Terminal corrosion or housing melting from exhaust heat causes intermittent O2 sensor signals, rich/lean fuel trim faults, and increased fuel consumption. Replacing the connector restores clean heater and signal circuit continuity.

Variant Guide

• 3.5mm Female – Bare 3.5mm pitch housing with terminals
• 3.5mm Female 15CM – 3.5mm housing with 15cm pre-wired leads
• 2.8mm Female – Bare 2.8mm pitch housing with terminals
• 2.8mm Female 15CM – 2.8mm housing with 15cm pre-wired leads

Select the pitch matching your OEM O2 sensor connector. Measure the terminal spacing or cross-reference OEM 1928404993 with your vehicle’s wiring diagram.

Installation Steps

1. Allow the exhaust system to cool completely before working near O2 sensors
2. Locate the O2 sensor connector in the exhaust harness (upstream or downstream of catalytic converter)
3. Disconnect the original connector and inspect terminals for heat damage or corrosion
4. Transfer terminals to the new housing or splice in the pre-wired variant
5. Reconnect and clear O2 sensor fault codes with a scan tool
6. Run the engine through a drive cycle to confirm sensor readiness

Frequently Asked Questions

Q: What fault codes indicate a failed O2 sensor connector?
A: Common codes include P0030/P0036 (O2 sensor heater circuit), P0130–P0167 (O2 sensor circuit range/performance), and P0420/P0430 (catalyst efficiency below threshold – often caused by a faulty upstream O2 sensor signal).

Q: How do I know if I need 2.8mm or 3.5mm?
A: Measure the terminal pitch (center-to-center spacing) of your existing O2 sensor connector, or cross-reference OEM 1928404993 with your vehicle’s wiring diagram. The 3.5mm variant is more common on European platforms; 2.8mm on Asian platforms.

Q: Is this compatible with wideband AFR sensors?
A: This 4-pin connector is compatible with standard narrowband and wideband O2/AFR sensors using the 4-pin configuration. Verify pin count and pitch before ordering.

Q: Does this include the sensor?
A: No. This is the connector housing and terminals only. The O2 sensor is sold separately.

Compatible Applications

• Universal 4-pin O2 / lambda sensor harness repair (OEM 1928404993)
• Upstream and downstream oxygen sensor connectors
• Air-fuel ratio (AFR) sensor harness replacement
• European and Asian platform O2 sensor circuits (2.8mm / 3.5mm pitch)