Battery - Jump Starting/Charging and Labels
TO: OUR MERCEDES-BENZ PASSENGER CAR DEALERSDATE: November 1993 (Supersedes SI. MBNA 54/40, Nov. 1992)
REF.NO. MBNA 54/40a
Revision: Model applicability, and revised text.
SUBJECT:
ALL MODELS
BATTERY JUMP-STARTING AND CHARGING
With the increasing number of complex electronic control modules in modern automobiles comes an increased risk of electronic component damage when working with the battery. To avoid damage to the vehicle's electrical system, certain procedures must be followed.
WARNING!
Batteries contain sulfuric acid and generate a highly flammable and explosive hydrogen gas. Always wear eye protection, preferably chemical safety goggles or a face shield when working on or near batteries. Never lean over a battery. Improper connecting or disconnecting of battery terminals, jumper cables or charger clamps can create sparks. A spark, flame or lighted cigarette can cause a battery to explode and cause serious facial/eye injuries. Never jump start or charge a frozen battery, this may cause the battery to explode. A frozen battery must be first thawed out before jump starting or charging.
Refer to S.I. MBNA 54/38 (October 1993) for a complete description of proper battery care and handling procedures.
Jump starting
CAUTION!
The power surges generated during a typical jump start are substantial. While the electronic components in all Mercedes-Benz automobiles are designed to withstand a normal jump-starting attempt, damage may occur if the incorrect procedure is used. Therefore, all service personnel are cautioned that Mercedes-Benz vehicles are to be jump started only from another 12 volt battery. The use of starting devices (such as boost-start chargers, free-standing generators, etc.) is likely to cause extensive damage to the electrical system and its components.
General procedure for jump starting from one vehicle to another (follow procedure in Owners Manual for specific vehicle applications)
1. Position the vehicle with the charged battery so that the jumper cables will reach, but never let the vehicles touch. Make sure the jumper cables do not have loose or missing insulation.
2. On both vehicles:
^ Turn off engine and all lights and accessories, except hazard warning flashers or work lamp.
^ Apply parking brake and shift selector lever to position "P".
Important!
3. Clamp one end of the first jumper cable to positive (+) terminal of the discharged battery and the other end to positive (+) terminal of the charged battery. Make sure the cable clamps do not touch any other metal pants.
4. Clamp one end of the second jumper cable to the grounded negative (-) terminal of the charged battery and the final connection to a grounded heavy metal bracket in the engine compartment or on the engine of the disabled vehicle (In case the disabled vehicle is a equipped with a trunk-mounted battery, make the final connection to either a grounded metal bracket or the battery ground wire where it attaches to the vehicle body.).
5. Start engine of the vehicle with the charged battery, switch off all unnecessary accessories and run at high idle. Make sure the cables are not on or near pulleys, fans, or other pants that will move when the engine is started. Then start engine of the disabled vehicle in the usual manner.
6. After the engine has started, remove jumper cables by exactly reversing the above installation sequence, starting with the last connection made first. When removing each clamp, make sure that it does not touch any other metal while the other end is still attached.
Jumper cable specifications
^ Minimum cable cross-section of 25 sq.mm or approx. 2 AWG
^ Maximum length of 11.5 ft. (3.5m).
Charging
CAUTION!
Always disconnect the battery from the vehicle's electrical system before connecting a battery charger. Most battery chargers generate voltage high enough to cause electrical system and component damage.
In all cases, the instructions in the owners manual should be followed. Damage caused by improper jump starting and/or charging is not covered under warranty, since this is considered a workshop risk.
Labeling
A warning label (Figure 1) is being installed in all models at the VPC. In case this label is missing or damaged, it may be ordered as a literature item through MB-NET. The labels are available individually
Parts
Label Locations