Description
Overview
This Valeo hazard warning switch is a direct-fit replacement designed to restore the operation of the hazard lights and the associated locking control on compatible PSA vehicles. It is commonly identified by part numbers 40377877, 6554L0 and 6554W9 and is frequently searched by these product codes, which makes locating the correct spare quick and reliable.
Key Benefits
- OE-quality fitment from a recognized supplier (Valeo).
- Restores reliable operation of hazard lights and central locking interface.
- Designed for straightforward, plug-and-play replacement.
- Suitable for professional workshops and competent DIY mechanics.
Function And Common Failure Modes
The switch controls the hazard warning circuit, activating all indicator lamps simultaneously when engaged. On some PSA dashboards it also incorporates or interfaces with the central locking control logic. Typical symptoms of a failing unit include no response when the switch is pressed, intermittent activation, stuck or loose actuator, or failure of the central locking signalling. Failures most often result from worn internal contacts, mechanical wear, water ingress or connector/cabling faults.
Replacement And Installation Notes
Replacement is a routine task for an experienced technician or a careful DIYer. Recommended steps:
- Disconnect the negative battery terminal before starting to prevent short circuits.
- Remove the trim panel surrounding the switch (some models require removal of additional dashboard trims).
- Unplug the electrical connector and release any retaining clips holding the switch in place.
- Fit the new unit, reconnect the plug and reassemble trims. Reconnect the battery and test the hazard lights and locking functions.
Check related fuses and wiring if symptoms persist after replacement. If uncertain, consult a professional technician to avoid dash damage or electrical faults.
Durability And Service Life
Service life depends on usage and environmental exposure. Switches exposed to moisture or heavy daily use will wear faster. Regular inspection of dashboard seals and connectors helps extend service life.
Technical Information
- Manufacturer: Valeo
- Model: Citroën Xsara Picasso (select models); also compatible with select PSA Citroën and Peugeot vehicles using the same part numbers
- Product Codes: 40377877, 6554L0
- Other Numbers: 6554W9
Note: Many buyers search by part number, so confirm fitment against your vehicle’s VIN or original part marking before purchase. If you need assistance identifying the correct part for your vehicle, contact a qualified parts specialist or your workshop.
