Applies to: Hyundai Coupe/Tiburon 1998-2001
Engine Electrical System Charging System
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  1. The maintenance-free battery is, as the name implies, totally maintenance free and has no removable battery cell caps.

  1. Water never needs to be added to the maintenance-free battery.

  1. The battery is completely sealed, except for small vent holes in the cover.

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The specific gravity of battery electrolyte changes with temperature. Heat thins the solution and lowers the specific gravity. Cold thickens the solution and raises the specific gravity.

A fully charged battery should have a specific gravity between 1.260 and 1.280, with the electrolyte temperature at 80F. The specific gravity reading must be corrected by adding 4 points (.004) for each 10F above 80F or subtracting 4 points for every 10F below 80F.

For example: The hydrometer reading is 1.280, and the electrolyte temperature reading is 10F. According to the chart below, the specific gravity must be lowered by 0.028 points. The true corrected reading is 1.252.

280 - 0.028 = 1.252

You should never take a hydrometer reading immediately after water has been added. The water and electrolyte must be mixed by either charging for a few minutes at a low rate or by allowing the battery to sit for an hour.

A difference of 50 points (0.050) or more between one or more cells indicates a defective battery. It should be replaced.
Charge method
Specific gravity
Slow charge (5A)
Fast charge (20A)
Below 1.100
14 hours
4 hours
100 - 1.130
12 hours
3 hours
130 - 1.160
10 hours
2.5 hours
160 - 1.190
8 hours
2.0 hours
190 - 1.220
6 hours
1.5 hours
Above 1.220
4 hours
1.0 hours
  1. Make sure ignition switch is in the Off position and all accessories are Off.

  1. Disconnect the battery cables (negative first).

  1. Remove the battery from the vehicle.

    Care should be taken in the event the battery case is cracked or leaking, to protect your skin from the electrolyte. A suitable pair of rubber gloves (not household type) should be worn when removing the battery.
  1. Inspect the battery carrier for damage caused by the loss of acid from the battery. If acid damage is present, it will be necessary to clean the area with a solution of clean warm water and baking soda. Scrub the area with a stiff brush and wipe off with a cloth moistened with baking soda and water.

  1. Clean the top of the battery with the same solution as described in Step (4).

  1. Inspect the battery case, and cover, for cracks. If cracks are present, the battery must be replaced.

  1. Clean the battery posts with a suitable battery post cleaner.

  1. Clean the inside surface of the terminal clamps with a suitable battery terminal cleaning tool. Replace damaged or frayed cables and broken terminal clamps.

  1. Install the battery in the vehicle.

  1. Connect the cable terminals to the battery post, making sure the top of the terminal are flush with the top of the post.

  1. Tighten the terminal nut securely.

  1. Coat all connections with light mineral grease after tightening.

    When batteries are being charged, an explosive gas forms beneath the cover of each cell. Do not smoke near batteries being charged or which have recently been charged. Do not break live circuits at the terminals of the batteries being charged. A spark will occur where the circuit is broken. Keep all open flames away from the battery.