What is the reason for the flashing snowflake and S in Citroen transmission failure?
3 Answers
The flashing snowflake and S on the dashboard are due to a transmission control system malfunction. In automatic transmission models, after severe mechanical failures such as engine idling, transmission slipping, clutch burnout, or inability to move despite acceleration, the transmission computer will activate a fault alarm, causing the transmission warning light to illuminate. Below is relevant information: 1. Causes of transmission failure: Sporadic or persistent faults in the automatic transmission's electronic components may cause the transmission warning light to flash intermittently or continuously as an alert, potentially leading to gear lock-up. Some models directly illuminate the small gear transmission warning light on the dashboard along with a text alert indicating transmission failure, allowing continued driving with limited acceleration capability. 2. Precautions: Analyze the current situation carefully and avoid blindly continuing to drive to prevent severe transmission damage. If the transmission warning light is on but no other abnormalities are observed, with engine speed and vehicle speed normal as usual, you may continue driving but should promptly arrange for a transmission fault diagnosis.
I've repaired many Citroën vehicles before, and when encountering the flashing snowflake S light issue, the common cause is usually internal transmission problems. The AM6 transmission used by Citroën is prone to minor issues, such as low fluid levels or poor-quality fluid. Over time, the fluid thickens, affecting lubrication and leading to jerky movements. Faulty sensors, like the speed sensor, can trigger false alarms, causing the light to flash incessantly. If the valve body gets stuck, gear shifts become rough and unsteady. Additionally, software glitches in the electronic control unit are common, possibly due to unstable voltage disrupting the program. Ignoring this issue can worsen the transmission's condition—mild cases result in strong jerking, while severe cases may lead to complete gear failure. Therefore, I recommend visiting a professional shop to check fluid levels and error codes, and try replacing the fluid first to avoid costly major repairs later. Regular maintenance is key—don’t wait for the light to flash before taking action.
As a car owner, I've experienced the annoyance of a flashing snowflake S light, often caused by simple issues. The main culprit is aged transmission fluid - if it hasn't been changed for six or seven years, it thickens and loses lubricity, triggering the warning. A faulty temperature sensor could also be to blame, with inaccurate readings causing false alarms. Loose connections or moisture in wiring may lead to poor contact and warning activation. This malfunction often manifests as jerky shifts or failed gear changes, which is quite frustrating. My advice is to start with low-cost solutions: check the transmission fluid's color and level, replacing it if blackened; try restarting the vehicle as temporary errors may resolve. If the light persists, promptly visit a repair shop for diagnostic scanning. Delaying repairs until valve bodies or motors fail means costly repairs - prioritize safety and don't wait until highway emergencies occur.
