Product Description

This air conditioning refrigerant pipe is a direct-fit solution for Citroën C4 Grand Picasso models equipped with the 1.6 HDi 9HZ engine and compatible variants. Frequently searched by OE numbers 9653505780 and 6477D5, the part connects key HVAC components and ensures reliable refrigerant circulation between condenser, evaporator and compressor. Designed for professional workshops and skilled DIYers, the description below highlights fitment, function, cause of failure and practical installation tips to help you decide and install with confidence.

Function And Application

The climate pipe routes refrigerant within the vehicle’s air conditioning system and maintains system pressure and flow. It supports the heat-exchange process that cools the passenger cabin and works in conjunction with hoses, fittings, O-rings and mounting brackets. Proper sealing and correct routing are essential to avoid leaks, loss of cooling performance or compressor damage.

Fitment And Compatibility

Main Fitment: Citroën C4 Grand Picasso (models with 1.6 HDi 9HZ engine). Cross-reference OE Numbers: 9653505780, 6477D5. The part is commonly searched by these product codes, so entering them in search fields will help you locate the correct item quickly. Verify model year and engine code against your vehicle documentation before installation.

Installation Recommendations

• Recover Refrigerant Safely: Always evacuate and recover A/C refrigerant using approved service equipment before disconnecting the pipe.
• Replace Sealing Elements: Fit new O-rings and seals at all connections. Lubricate O-rings with the correct PAG oil specified by the manufacturer to ensure proper sealing.
• Torque And Routing: Reuse original mounting points and clamps. Tighten fittings to the manufacturer’s torque values to avoid distortion or leaks.
• Leak And Pressure Test: Perform a pressure/leak test after installation. Use electronic leak detection or UV dye as appropriate.
• Evacuate And Recharge: Evacuate the system to the recommended vacuum level and recharge with the refrigerant type and quantity specified by the vehicle manufacturer.
• Professional Service Recommended For Refrigerant Handling: Handling refrigerant requires certified A/C service equipment and, in many jurisdictions, certified technicians.

Most Common Causes Of Failure

Climate pipes typically fail due to corrosion, mechanical damage or deteriorated seals. Common failure modes include:

• Corrosion from road salt or moisture leading to pinhole leaks.
• Vibration and chafing where the pipe contacts brackets or nearby components, causing cracks.
• Age-related hardening or compression of O-rings and sealing surfaces resulting in refrigerant leaks.
• Impact damage from road debris or improper previous installations.

Technical Information

• Manufacturer: Stellantis (Citroën/Peugeot)
• Model: Citroën C4 Grand Picasso
• Product Codes: 9653505780, 6477D5
• Additional Numbers: 6477D5 | 9653505780

Notes For Purchase

Searchable by OE numbers 9653505780 and 6477D5 — enter these codes to quickly find the correct item. Ensure engine code (1.6 HDi 9HZ) and vehicle model match the listing before ordering. If replacing the pipe, plan to replace O-rings and perform a full evac/recharge cycle to restore correct system function and longevity.