There are many crucial factors that can cause a fuel pump relay to overheat, and in doing so affect how well the relay performs its job. The most common reason, and likely culprit is due to high current draw from the fuel pump itself. A unit in which a pump is suddenly faced with more resistance or has become clogged may require as much as 30% more current than it would under optimal conditions. This extra load drafts makes the relay to buy while this can lead to a possible failure. According to automotive expert Sam Richards, “Relays can be expensive if they overheat and then cease to function due to high current draw.
The other culprit that causes overheating in relays is bad connections. If the wiring is corroded or not connected properly, an electrical resistance can be formed. A report by the Electrical Reliability Services said that poor connections are responsible for as many as 1 in 4 of all electrical failures in automotive systems. This locations a pressure junction of excessive resistance and this warmth may cause them to fail or breakdown the insulation at the relay, in that case it doesn’t heat yet as an alternative burns causing limited bloodless airflow.
Not allowing proper air circulation around the relay might also contribute to overheating. Universal — Most vehicles have a small engine bay that doesn’t allow much heat to escape. Especially, when the ambient temperature is over 80°F(27°C), the relay components will be much hotter with being used under high temperature environment. According to the National Highway Traffic Safety Administration, electrical parts have a 50 percent reduction in life when exposed to high tempertures for an extended period.
Also, the age of the relay counts. The innards of old relays may be worn out, which can cause increased internal resistance and poor current handling. An old relay of more than five years will wear, and cause low temperature thermal conduction from oxide formation. Almost 15 % of relay failures are a result of aging and worn-out parts according to studies.
Another factor that may cause relay overheating is a fuel pump that has malfunctioned. A bad fuel pump will not maintain the required pressure and cause the relay to cycle on then off. This high cycling will in turn pull a lot of perturbation within relay which will make is hot and heat generate during relay fail. A Society of Automotive Engineers report says that close to 20% of fuel pump relay failures happen as a consequence of problems related to the pump.
To wrap things up, a fuel pump relay can overheat because the amount of electricity consumed to open and close the circuit is too high, bad connections in any part of the circuit for too long, lack of ventilation around them or due to certain parts getting old with time and even failure by another part such as a fuel pump. Knowing about these factors can be useful to diagnose and prevent relay overheating problems. Visit Fuel Pump for more efficient fuel pump solutions.