4-Pin 6.3mm Unsealed Female Connector – Motorcycle High-Current Harness Yazaki 7123-2249

Direct-fit replacement for Yazaki part number 7123-2249, a 4-pin 6.3mm pitch unsealed female connector used for high-current motorcycle harness applications including relay sockets, fuse box connections, starter relay harness, and lighting power distribution circuits. The large 6.3mm terminal pitch handles up to 20A continuous current per pin.

Key Specifications

• Part Number: 7123-2249 (Yazaki)
• Pin Count: 4
• Gender: Female (with wire)
• Terminal Pitch: 6.3mm
• Wire Gauge: 16 AWG (1.5 mm²)
• Wire Length: 5.5 inches (140 mm)
• Sealing: Unsealed (interior / protected harness location)
• Housing Material: PA66 glass-filled nylon
• Terminal Material: Copper alloy, tin-plated
• Current Rating: Up to 20A per pin

Relay Socket Pin Assignment (4-Pin, ISO 280)

Note: Pin assignment varies by application. Verify with vehicle-specific wiring diagram before installation.

Yazaki 7122 vs 7123 – Male vs Female

In Yazaki part numbering, 7122-xxxx = male housing (pin side) and 7123-xxxx = female housing (socket side). The mating male connector for 7123-2249 is 7122-2249.

Compatible Applications

• Motorcycle relay socket: Main relay, fuel pump relay, starter relay harness connector
• Fuse box harness: Power distribution and fuse block connector
• Lighting power: Headlight relay and high-current lighting harness connector
• Honda / Yamaha / Kawasaki / Suzuki: High-current body harness connectors

Diagnosis – Relay Circuit Faults

• Relay not engaging: Check 12V at Pin 86 (coil supply) and continuity at Pin 85 (coil ground) – an open circuit at either pin prevents relay activation
• Voltage drop under load: Measure voltage at Pin 30 and Pin 87 under full load – >0.2V drop indicates high contact resistance from a corroded 6.3mm terminal
• Connector melting: Caused by sustained high contact resistance – replace connector and verify terminal crimp quality and wire gauge match

FAQ

Q: What is the mating male connector for Yazaki 7123-2249?
A: The mating male connector is 7122-2249 (Yazaki). Confirm pin count and housing profile match before ordering.

Q: Can I use a 2.8mm connector instead of 6.3mm for a relay socket?
A: No – the 2.8mm terminal is rated for 9A maximum. Using it in a 20A relay circuit will cause overheating and connector failure. Always match the terminal pitch and current rating to the circuit requirements.

Package Contents

1 × 4-Pin Female Connector (7123-2249) with 16 AWG wire and terminal insert