How to Troubleshoot a Toyota Battery With No Lights
- 1). Put on a pair of plastic gloves and remove the battery caps from the top with a standard screwdriver and add distilled water to bring the level to the bottom of the filler rings, if necessary. Inspect the battery case and terminals for damage and corrosion. The battery case, top and cable connections should be free of grime. If the battery case is damaged, replace it.
- 2). Set your multimeter to the 20 DCV range, turn on the meter and hook the red probe to the positive battery post (red cable) and the black probe to the negative battery post (black cable). Your meter should read close to 12.6V, if your battery is charged. If the charge is sufficient, the problem might be in the battery connections or fuse box. Otherwise, charge the battery and try starting your Toyota.
- 3). Disconnect the positive (red) battery cable with a wrench. Switch your multimeter to the 20m DCA range. Make sure the ignition key is off. Connect the red probe to the positive battery post and the black probe to the battery cable terminal you just disconnected. Your meter should read 10 mA or less. Otherwise, you need to locate the component or system draining power from the battery.
- 4). Put on your plastic gloves and remove the battery caps with a standard screwdriver. Check the electrolyte in each battery cell with a hydrometer, following the instructions from the tool manufacturer. If you get a reading of 1.265 or more in every cell, your battery is charged and in good condition. A lower reading of 1.265 in every cell usually indicates a discharged battery. Slow charge the battery and repeat this step. However, if any of the cell readings are off by 25 to 50 points compared to any of the other cells, you need to replace the battery.
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