Procedures
Battery Charging
WARNING: Before beginning any service procedure, REFER to Safety Warnings . Failure to follow this instruction may result in serious personal injury.
Battery Charging Overview
Batteries discharge while the vehicle is on the dealer lot or parked by the customer for an extended period of time due to normal parasitic key-off loads. Also, vehicles still in dealer inventory or in long-term storage may be driven short distances with heavy electrical loads. Over a period of time (30 days or more), this could result in vehicles having shallow or deeply discharged batteries.
- Deeply discharged- A battery that is drained over a prolonged period of time, such as an unsold vehicle or a vehicle in storage, to the point the battery is dead.
- Shallow discharge- A battery that is drained by leaving an accessory on for several hours or a few days and has a very low charge.
The vehicle charging system is designed to supply the electrical power needed to maintain the battery near full charge during normal vehicle use. The charging system is not capable of bringing a deeply discharged battery back to near full charge in a short amount of time such as allowing the vehicle to idle for 15 minutes to "recharge the battery." Discharged batteries should be charged using an external charger.
NOTE: Battery chargers have improved greatly with the addition of the new generation pulse chargers. These chargers pulse current into the battery, breaking down the sulfation layer on the battery plates and generally reduce charging times to less than an hour.
NOTE: Cold batteries will not readily accept a charge. Therefore, batteries should be allowed to warm to approximately 5°C (41°F) before charging. This may require 4 to 8 hours at room temperature.
The following chart summarizes 2 recommended methods of charging.
Charger Connected to Negative Battery Terminal
WARNING: Do not attempt to service, charge, recharge or jump start a battery unless the following information has been read and understood. Failure to follow this instruction may result in serious personal injury.
WARNING: Batteries contain sulfuric acid and produce explosive gases. Work in a well-ventilated area. Do not allow the battery to come in contact with flames, sparks or burning substances. Avoid contact with skin, eyes or clothing. Shield eyes when working near the battery to protect against possible splashing of acid solution. In case of acid contact with skin or eyes, flush immediately with water for a minimum of 15 minutes, then get prompt medical attention. If acid is swallowed, call a physician immediately. Failure to follow these instructions may result in serious personal injury.
NOTE: When charging the vehicle battery by connecting the charger with the battery disconnected, the BCM (Body Control Module) will not immediately update the battery state of charge. In this instance, after charging, you must carry out the BMS (Battery Monitoring System) Reset using the scan tool once the battery is reconnected.
1. Connect the positive (red) charger clamp to the positive battery post (battery disconnected) or cable end (battery connected).
2. Connect the negative (black) charger clamp to the negative battery post (battery disconnected) or the negative battery cable crimp near the battery cable end (battery connected).
3. Charge the battery according to the battery charger manufacturer's operating instructions.
4. After charging of a disconnected battery only is complete, carry out the BMS (Battery Monitoring System) Reset using the scan tool once the battery is reconnected.
Charger Connected to Engine or Chassis Ground
WARNING: Do not attempt to service, charge, recharge or jump start a battery unless the following information has been read and understood. Failure to follow this instruction may result in serious personal injury.
WARNING: Batteries contain sulfuric acid and produce explosive gases. Work in a well-ventilated area. Do not allow the battery to come in contact with flames, sparks or burning substances. Avoid contact with skin, eyes or clothing. Shield eyes when working near the battery to protect against possible splashing of acid solution. In case of acid contact with skin or eyes, flush immediately with water for a minimum of 15 minutes, then get prompt medical attention. If acid is swallowed, call a physician immediately. Failure to follow these instructions may result in serious personal injury.
1. Connect the positive (red) charger clamp to the positive battery post.
2. NOTE: The negative charger clamp must be connected to an unpainted chassis surface or a solid engine component such as a generator mount or engine lifting eye.
Connect the negative (black) charger clamp to an engine or chassis ground.
3. Charge the battery according to the battery charger manufacturer's operating instructions.