Description
Complete BEHR Digital Air Conditioning Harness for Peugeot 307 from 2004.
High-quality OEM BEHR wiring harness designed for the digital climate control system of the Peugeot 307 (from 2004). This complete A/C harness (Behr T5) replaces the factory loom that connects the climate control unit to the blower motor, actuators, compressor clutch and relevant sensors. Ideal for professional garages and experienced DIY mechanics who need a direct-fit solution with original-spec connectors and reliable signal paths. Commonly searched by part numbers 42991 and 643642 — include these references when locating the correct item.
Technical Information
- Manufacturer: BEHR
- Model: Peugeot 307 (2004)
- Product Codes: 42991, 643642
- Additional Numbers: Behr T5, Stellantis / CITROËN / PEUGEOT, NFP
Compatibility and Fitment
Designed primarily for Peugeot 307 models from 2004 equipped with the BEHR digital climate control system. The harness follows OE routing and connector types used by Stellantis on compatible BEHR T5 climate systems. Confirm compatibility by matching part numbers 42991 or 643642 with the vehicle’s existing harness.
Function
The harness supplies power and signal connections between the climate control head unit and the following components: blower motor, heater/air-mix actuators, A/C compressor clutch, evaporator temperature sensor, and condenser/cooling fan circuits. It ensures correct communication and power distribution so the climate system regulates cabin temperature and compressor operation reliably.
Installation Recommendations
- Disconnect the negative battery terminal before starting work to prevent short circuits and protect electronic components.
- Remove trim panels and center console pieces to access the climate control unit and harness routing.
- Label connectors if necessary, unplug mating connectors carefully, and release all retaining clips or grommets before removing the old harness.
- Route the new harness following original cable clips and mounting points; avoid tight bends and areas of potential chafing.
- Ensure all connectors are fully seated and locking tabs engaged. Reconnect the battery and verify climate functions (blower stages, flap actuators, compressor engagement, control display) before final reassembly.
- After installation, clear any stored fault codes and monitor system operation for intermittent faults.
Most Common Failure Reasons
- Connector Corrosion Or Moisture Ingress — Exposure to water or humidity causes poor contacts and intermittent faults.
- Mechanical Damage And Chafing — Rubbing against bodywork or sharp edges wears insulation and causes short circuits.
- Heat And Vibration — Prolonged engine bay heat and vibration can weaken solder joints or crimp connections over time.
- Previous Poor Repairs — Non‑OEM splices, incorrect crimps or unsecured repairs lead to early failures.
- Rodent Damage — Chewing or nesting in engine bay areas can sever wires or damage insulation.
Lifespan And Replacement Indicators
Service life depends on vehicle environment and maintenance. Replace the harness if you experience intermittent climate control operation, blower not working on all speeds, compressor not engaging despite correct commands, visible wiring damage, or persistent fault codes relating to climate sensors or actuators. Replacing the entire harness restores original routing and connector integrity, often resolving intermittent electrical faults.
Who Should Install
Recommended for professional auto-electricians and experienced DIY mechanics. Proper routing, secure connections and electrical testing are essential for reliable operation of the climate system.
