Computer Failure Problems of Volvo V70

I noticed the tail light brake bulbs were burning out quickly. After getting a ticket I stoped driving it until I could determine the cause. Volvo lists a brake relay recall. Brake light fuses and relays are in 4 locations in the car. They are: 1. Under the hood in the engine control unit ecu, 2. The passenger compartment a. Central control unit ccu and b. Fuse panel by drivers side door post 3. Rear control unit in the cargo compartment. The problem was an electrical engineering design where a steel race that surrounds the taillight bulbs transfers the electrical current is designed to fail. As the bulb heats up it transfers the heat to the plate and plastic pins that hold it in place under pressure from the spring steel parts of the removable bulb socket unit. As the plastic pins weaken and move away under pressure and heat from the bulb socket spring steel keepers, and conductors of voltage and current, the current is throttled down to a pin point as the plate moves away from the bulb creating more heat and arcing to melt the steel race surround the bulbs that supply the current. The replaced bulbs seem to work for a short time as the connection is reestablished when the bulb socket is removed and replaced, and the connection is reestablished for a time, but it will soon over heat and fail from the weakened and melted plastic lens. Brake light failure results not from a failed part, relay, fuse or wire, but from an engineering design flaw that was recognized and eliminated in the 2005 models. Ford and Volvo never mention this. A recall could amount to six hundred to a thousand dollars per car for the 4 lenses with labor. The arcing in the wiring may also cause other computer failures as the transmission also has an electrical problem in the kickdown process that causes an abnormal delay in neutral gear and hard engagement of the lower gear.

See all problems of the 2001 Volvo V70 🔎.