Battery discharge is a common problem we encounter during repairs. This type of fault is tedious to repair and difficult to pinpoint. Therefore, encountering this type of problem can be quite frustrating.

The most effective method for identifying a battery discharge is to use an inductive current clamp to measure the static current and identify the fault location.

Case Study: A glove box switch malfunction caused a severe battery discharge.

A customer described a severe battery discharge in a Sagitar 1.6 with 30,000 kilometers of mileage after three days of storage, which resulted in difficulty starting the vehicle.

After the vehicle arrived at the repair shop, we first tested the battery’s static voltage with a VAS5051, finding a normal static voltage of around 12.5V. (The customer had driven the vehicle.)

Using a 50A current clamp on the VAS5051, we measured the current and found that after turning off the ignition, the current gradually dropped from 0.691A to 0.268A and stopped decreasing.

Based on past repair experience, when the ignition is turned off and no electrical devices are active or leaking, the static current should be very low, approximately 0.01 to 0.05A, which is normal.

First, we checked obvious electrical devices (lighting, radio, etc.). Suddenly, we noticed that the light in the passenger-side glove box was constantly on, regardless of the switch.

After removing the glove box light bulb, the current dropped to a range of -0.034A to 0.02A, which is normal.

Replacing the glove box switch cleared the problem.