2.5 Series Automotive Waterproof Connector – 1–6 Pin Male & Female Plug for Haltech, MAP, TPS & GM Sensor Wiring

2.5 series (2.5mm pitch) automotive waterproof connectors — the compact sealed connector standard used by Haltech ECUs, GM (General Motors) OEM sensor harnesses, and aftermarket performance sensor wiring. The 2.5mm pitch provides a smaller housing than the AMP Type 1.5 series while maintaining IP67 waterproofing and automotive-grade temperature resistance. Widely used in motorsport ECU harness builds for MAP sensor, TPS (throttle position sensor), coolant temperature, and other sensor connections that require compact, sealed connectors compatible with Haltech and GM OEM pinouts.

Key Specifications

• Series: 2.5 series (2.5mm pitch)
• Pin Configurations: 1, 2, 3, 4, 6 pin (select above)
• Current Rating: 7A per contact
• IP Rating: IP67
• Operating Temperature: -40°C to +125°C
• Housing Material: PA66 nylon, flame retardant
• Contact Material: Copper alloy, tin-plated
• Wire Range: 20–22AWG

Haltech ECU Connector Compatibility

Haltech ECUs (Elite series, Nexus series) use 2.5 series connectors for many sensor inputs and outputs. Common Haltech applications:

• 3-pin: MAP sensor (supply + signal + ground), coolant temperature sensor, intake air temperature sensor
• 4-pin: TPS (throttle position sensor) with dual-track output, wideband O2 sensor controller connections
• 6-pin: Multi-function sensor clusters, fuel pressure + temperature combined sensors
• Always verify the specific Haltech ECU pinout documentation for your model before wiring — pin assignments vary between ECU generations.

GM OEM Sensor Connector Applications

General Motors uses 2.5 series compatible connectors on many OEM sensors across multiple vehicle platforms:

• MAP sensors: 3-pin 2.5 series on LS-series engines (LS1, LS2, LS3, LS7) and many other GM applications
• TPS: 3-pin on carbureted and early EFI applications; 6-pin on dual-track TPS for drive-by-wire systems
• Coolant temperature: 2-pin on most GM coolant temperature sensors
• Verify the specific GM part number and connector type against the vehicle service manual before ordering replacement connectors.

Frequently Asked Questions

What is the difference between 2.5 series and AMP Type 1.5 connectors?

AMP Type 1.5 series (1.5mm pitch) is smaller than 2.5 series (2.5mm pitch). Both are IP67 automotive waterproof connectors, but they use different contact sizes and are not interchangeable. 2.5 series connectors are used by Haltech and GM; AMP Type 1.5 is used by HID ballasts and other automotive lighting applications. Verify which series your ECU or sensor uses before ordering.

What crimp tool is required for 2.5 series contacts?

A dedicated 2.5 series crimp tool with the correct die for the contact size. Using the wrong crimp tool produces an incomplete crimp that fails pull-out testing and causes intermittent connections under vibration. For motorsport harness builds, use a ratchet crimp tool with 2.5 series dies — the ratchet mechanism ensures consistent crimp force on every contact.

Can I use 2.5 series connectors for Haltech wideband O2 sensor wiring?

Yes, for the sensor-to-controller connection. Wideband O2 sensors (Bosch LSU 4.9, NTK L2H2) typically use a 6-pin connector at the sensor body. The controller-to-ECU connection uses the ECU’s native connector type (2.5 series for Haltech). Verify the wideband controller’s connector type before ordering — some controllers use different connector series.

Typical Applications

• Haltech ECU harness: MAP, TPS, coolant temp, and sensor input connections
• GM LS engine swaps: OEM sensor connector replacement and extension harnesses
• Motorsport: Compact sealed sensor connections in weight-sensitive race car harnesses
• Performance tuning: Aftermarket sensor additions to OEM harnesses
• Automotive repair: Replacement connectors for damaged GM OEM sensor harnesses

Package Contents

Male plug housing + female socket housing (pin count as selected). Contacts and wire seals included. Quantity as selected.