Weather Pack connectors are the gold standard for sealed electrical connections in automotive, marine, and outdoor applications. Originally developed by General Motors (Delphi/Aptiv), they've become an industry-wide standard for any connection that needs to survive moisture, vibration, and temperature extremes.
This guide covers how Weather Pack connectors work, the sealing system, terminal types, and how to crimp them correctly.
What Is a Weather Pack Connector?
A Weather Pack connector is a sealed, multi-pin electrical connector designed for harsh environments. The key feature is its dual sealing system:
- Individual wire seals: Silicone seals on each wire entry point
- Connector face seal: A silicone mat seal between the mating connector halves
Together, these seals create an IP67-rated connection — dust-tight and protected against temporary immersion in water up to 1 meter.
Weather Pack connectors are used wherever standard connectors would fail due to moisture, road splash, engine bay heat, or vibration.
Weather Pack Sealing System
Wire Seals (Cavity Seals)
Each wire entry has a silicone seal that grips the wire insulation. The seal:
- Compresses around the wire when the terminal is inserted
- Prevents water from entering along the wire
- Must match the wire diameter — wrong size = no seal
Wire seals are color-coded by wire diameter:
| Color | Wire Diameter |
|---|---|
| Green | 0.35–0.5 mm² (22–20 AWG) |
| Blue | 0.5–1.0 mm² (20–18 AWG) |
| Red | 1.0–2.0 mm² (18–14 AWG) |
| Yellow | 2.0–3.0 mm² (14–12 AWG) |
Face Seal
The connector face seal is a silicone mat with holes for each terminal. When the two connector halves mate, the face seal compresses between them, sealing the entire mating interface.
Cavity Plugs
Unused cavities must be filled with cavity plugs — solid silicone inserts that maintain the face seal integrity. Never leave empty cavities unsealed.
Terminal Types
Weather Pack connectors use two terminal types:
Crimp Terminals (Standard)
- Crimped onto the wire using a Weather Pack crimping tool
- Available in male (pin) and female (socket) versions
- Sizes: 0.35 mm², 0.5 mm², 0.8 mm², 1.0 mm², 2.0 mm², 3.0 mm²
- Material: Tin-plated copper
Sealed Terminals
Some Weather Pack terminals have an integrated wire seal — the seal is part of the terminal rather than a separate component. These are used in high-volume OEM applications.
Connector Configurations
Weather Pack connectors are available in 1 to 12 circuit configurations:
| Circuits | Common Use |
|---|---|
| 1-pin | Single wire sealed connection |
| 2-pin | Sensor power + ground |
| 3-pin | Sensor with signal wire |
| 4-pin | Common for relays, actuators |
| 6-pin | Multi-function sensors, modules |
| 8-pin | ECU connections, complex sensors |
| 12-pin | Large modules, body control |
The connector housing is available in inline (both halves are plugs) and panel-mount (one half mounts to a panel or bracket) configurations.
Crimping Weather Pack Terminals
Correct crimping is critical for Weather Pack reliability. The terminal has two crimp zones:
Wire Crimp (Conductor Crimp)
- Crimps onto the stripped wire conductor
- Creates the electrical connection
- Must be gas-tight — no loose strands
Insulation Crimp (Strain Relief)
- Crimps onto the wire insulation
- Provides mechanical strain relief
- Prevents the wire from pulling out of the terminal
Crimping Process
- Strip the wire: 5–6 mm of insulation (check terminal spec)
- Slide on the wire seal: Thread the wire through the seal before crimping
- Insert wire into terminal: Conductor into the wire crimp barrel
- Crimp the terminal: Use a Weather Pack crimping tool (or equivalent ratchet crimper with correct die)
- Inspect the crimp: No loose strands, no cut strands, insulation crimp grips the jacket
- Insert into housing: Push terminal into cavity until it clicks (terminal position assurance)
- Verify seating: Gently tug the wire — it should not pull out
Crimping Tools
Weather Pack terminals require a specific crimping tool. The standard tool is the Delphi/Aptiv Weather Pack crimper (part 12085115 or equivalent). Generic ratchet crimpers with the correct die set also work.
Do not use:
- Pliers (inconsistent crimp, no strain relief)
- Standard automotive crimpers (wrong die geometry)
- Soldering (defeats the purpose of a crimp terminal)
Assembly Sequence
The order of assembly matters:
- Thread wire through the connector housing (back-to-front)
- Thread wire through the wire seal
- Strip wire insulation
- Crimp terminal onto wire (with seal already on wire)
- Insert terminal into housing cavity until it clicks
- Verify terminal is locked (TPA — Terminal Position Assurance)
- Install cavity plugs in unused cavities
- Mate the two connector halves
Disassembly
To remove a terminal from a Weather Pack housing:
- Use a terminal removal tool (pick or flat blade) to depress the terminal locking tab
- Push the terminal out from the front of the housing
- Do not pull the wire — push the terminal
Forcing terminals out without releasing the lock damages the housing and terminal.
Weather Pack vs Other Sealed Connectors
| Connector | IP Rating | Circuits | Typical Use |
|---|---|---|---|
| Weather Pack | IP67 | 1–12 | Automotive, marine, outdoor |
| Deutsch DT | IP67 | 2–12 | Heavy-duty, off-road, industrial |
| Deutsch DTM | IP67 | 2–12 | Automotive, motorsport |
| Superseal 1.5 | IP67 | 1–6 | Automotive (TE Connectivity) |
| AMP Econoseal | IP54 | 2–12 | Automotive (lower sealing) |
Weather Pack is the most widely available and lowest-cost sealed connector. Deutsch DT/DTM offers higher current ratings and more robust construction for heavy-duty applications.
Common Applications
- Engine sensors: Coolant temperature, MAP, MAF, O2 sensors
- Transmission: Solenoids, speed sensors
- Body electrical: Door modules, window motors, lighting
- Marine: Bilge pumps, navigation lights, engine connections
- Trailers: Lighting, brake controllers
- Solar/off-grid: Battery connections, charge controller wiring
- Custom builds: Hot rods, race cars, camper vans
Troubleshooting
High resistance / intermittent connection:
- Check for corroded terminals — replace if green/white oxidation present
- Verify crimp quality — re-crimp or replace terminal
- Check wire seal is correct size and properly seated
Water intrusion:
- Verify cavity plugs are installed in all unused cavities
- Check face seal is not damaged or missing
- Verify wire seals are correct size for wire diameter
Terminal won't lock:
- Check terminal is fully inserted — should click audibly
- Inspect housing for damage to locking tab
- Verify correct terminal for housing (male/female, size)
Summary
Weather Pack connectors provide reliable IP67 sealing for automotive and outdoor electrical connections through a dual-seal system (wire seals + face seal). Key points:
- Match wire seals to wire diameter — wrong size means no seal
- Fill all unused cavities with cavity plugs
- Use the correct crimping tool — pliers produce unreliable connections
- Follow the correct assembly sequence (seal on wire before crimping)
- Available in 1–12 circuit configurations for most automotive applications
CZT supplies waterproof automotive connectors, sealed terminals, and wire harness components. Browse our automotive connector range for Weather Pack compatible products and accessories.
