What is the cause of the u140600 no-load current too high fault?
2 Answers
u140600 no-load current too high fault may be caused by leakage leading to excessive current. Use an ammeter to measure the battery output current to determine if there is leakage or short circuit in the electrical system. When the vehicle is in the power-off state, the standby current should be at most a few tens of milliamperes. Related introduction: First, check whether the power supply circuit of the original vehicle host is interfered. You can try to supply power separately from the battery, avoiding the original wiring, onboard computer, relays and other interference sources as much as possible. If possible, a power filter can also be installed. If the current noise still cannot be eliminated, seek professional maintenance and repair.
As a veteran mechanic with decades of experience, I've dealt with numerous U140600 no-load current overcurrent faults. There are three most common causes: First, internal battery short circuits, which continue to drain power after the car is parked, resulting in abnormal current; Second, alternator issues, particularly voltage regulator failure, causing it to output high current even under no-load conditions; Third, control module malfunctions, such as the body control unit or ECU failing to enter proper sleep mode, maintaining power consumption. For diagnosis, I always start by measuring quiescent current: After locking the vehicle, wait 15 minutes and use a multimeter to check the current at the battery negative terminal - anything exceeding 50mA indicates abnormality. Troubleshoot step by step: First check fuses for parasitic current sources like unactivated anti-theft systems or short circuits; Then inspect alternator output and module programming. In repair shops, we typically replace old batteries or update software first, only replacing modules if those don't work. Owners should regularly check battery lifespan to prevent worsening faults that could affect driving safety.
