Isuzu KB P190. Manual - part 912

Battery 

Page 6D1-3–8 

 

Step Action 

Yes 

No 

5 

Perform the hydrometer test, refer to 3.3 

Hydrometer Test. 

Is the battery fully charged? 

Go to Step 6 

Fully charge the 

battery, refer to 4.2

 Battery 

Charge 

6 

Load test the battery, refer to 3.4 

Load Test. 

Does the battery pass the load test? 

Battery Serviceable. 

Refer to:  

6D1–1 Charging 

System – V6. 

Replace the battery, 

refer to 4.1

 Battery 

When all diagnosis and repairs are completed, check the system for correct operation. 

3.2 Battery 

Inspection 

1 

Read and obey the safety precautions for working with batteries, refer to 2  Safety Precautions. 

2 

Check the battery terminals and around the battery area for corrosion deposits. Remove any deposits as follows: 

a 

Scrub the area with a stiff brush. 

b 

Treat the area with a solution of warm water and baking soda or ammonia. 

c 

Rinse with clean water. 

3 

Check the battery posts, if they are loose, burned, pitted or damaged in any way replace the battery. Refer to 4.1
 Battery. 

4 

Check the battery case, if it is cracked or damaged replace the battery. Refer to 4.1  Battery. 

5 

Remove each filler cap (1) and check the electrolyte 
level is at the bottom of the filler-neck tube (2). 

6 

If the level is low, carefully add distilled water to the 
cell until the level reaches the bottom of the filler-neck 
tube. 

N O T E  

Do not overfill the cells, but maintain the level at 
least 20 mm above the separator plates (3). 

7 

If the electrolyte usage seems excessive, check the 
battery case is not faulty. 

N O T E  

Normal electrolyte usage is less than 30 ml per 
10,000 kilometres (or slightly more for long, 
continuous running or in high temperatures). 

Figure 6D1-3 – 2 

Battery 

Page 6D1-3–9 

 

8 

Ensure the battery hold-down bolts (2 & 3) and bracket 
(1) firmly secure the battery. 

Battery hold-down bolt 
torque specification ...................................8.0 – 10.0 Nm 

9 

Check the cable insulation for damage or wear along 
the cable. Replace the cable as required. 

10 

Check the cables do not have broken or frayed 
strands and are secure in the terminals. Repair as 
required. 

Figure 6D1-3 – 3 

11 

Ensure the terminal clamp (2) sits below the top of the 
battery post (1). 

12 

Check the terminal clamps are attached to the battery 
posts securely. Replace the terminals as required. 

13 

Tighten the terminal clamp nuts to the correct torque 
specification. 

Battery terminal nut 
torque specification .....................................2.0 – 5.0 Nm 

14 

Smear the battery posts and terminals with petroleum 
jelly to resist corrosion. 

Figure 6D1-3 – 4 

3.3 Hydrometer 

Test 

As a lead-acid battery discharges, sulphur elements in the electrolyte move from the electrolyte solution into the lead 
battery plates. This removes the sulphuric acid from the electrolyte and changes it to water. Therefore the concentration 
of sulphuric acid in the electrolyte indicates the state of charge. 

The concentration of sulphuric acid can be measured using a hydrometer. The state of charge is measured in terms of 
specific gravity; the lower the specific gravity reading, the lower the state of charge. 

N O T E  

If distilled water has been added to the battery, 
do not use the hydrometer until the battery has 
been charged for at least 30 minutes. 

1 

Read and obey the safety precautions for working with batteries, refer to 2  Safety Precautions. 

2 

Remove the battery filler caps. 

3 

Force the air out of the hydrometer bulb. 

4 

Hold the hydrometer vertically in the cell with the pick-up tube submerged. 

5 

Draw in sufficient liquid to lift the hydrometer float freely when the bulb is fully released. 

Battery 

Page 6D1-3–10 

 

6 

Still holding the hydrometer vertically, record the reading. 

7 

Put the electrolyte back into the cell. 

8 

Repeat steps 3 to 7 for each cell. 

9 

Determine the temperature of the battery by 
temporarily placing a thermometer (1) into one of the 
cells (2). 

10 

Install the battery filler caps. 

11 

Calculate the temperature-compensated readings: add 
0.004 for every 5

°C above 27°C or subtract 0.004 for 

every 5

°C below 27°C. 

12 

Determine the state of charge of the battery using the 
temperature-compensated readings and the table 
below. 

N O T E  

The specific gravity of a charged battery should 
not vary more than 0.025 between cells. Larger 
variations indicate defective cells and the battery 
must be replaced, refer to 4.1 Battery. 

Figure 6D1-3 – 5 

 

Battery Condition 

Specific Gravity Reading

Fully charged 

1.240 to 1.260 

Requires charging 

<

 1.190 

Fully discharged 

1.110 to 1.130 

3.4 Load 

Test 

Load testing the battery with a high rate discharge (HRD) tester simulates using the starter motor and checks if the 
battery is in serviceable condition. The battery must be at least 65% charged before commencing this test. 

N O T E  

HRD testers are available with either fixed or 
variable loads. The operating procedures may 
vary from brand to brand, therefore follow the 
manufacturer’s instructions. 

High Rate Discharge Load Test 

1 

Read and obey the safety precautions for working with batteries, refer to 2  Safety Precautions. 

2 

Ensure the state of the battery is at least 65% charged. Refer to 3.3 

Hydrometer Test. 

3 

Refer to Warning, Caution and Notes in this section, before disconnecting the battery. 

4 

Disconnect the battery negative terminal. 

5 

Disconnect the battery positive terminal. 

6 

Connect the HRD tester to the battery terminals ensuring correct polarity. 

7 

Set the tester switches to suit the battery size. 

Fixed load tester: 

a 

Apply the load for approximately 10 seconds to remove any surface charge. 

b 

Wait 15 seconds for the battery to recover. 

Variable load tester: 

a 

Apply a 300 A load for approximately 15 seconds to remove any surface charge. 

Battery 

Page 6D1-3–11 

 

b 

Wait 15 seconds for the battery to recover. 

8 

If possible, set the selector to 50% of rapid discharge current (or three times the 20 hour discharge rate). 

9 

Apply the load test for 10 seconds and record the battery voltage. If one cell is faulty it will gas excessively or 
overheat. This indicates a faulty battery. 

10 

Recharge the battery if the voltage is at or below the minimum voltage specified by the HRD manufacturer (or 
9.6 V). 

11 

Replace the battery if the voltage is below the minimum voltage specified by the HRD manufacturer (or below 9.6 V 
after the battery is charged and the test is repeated). Refer to 4.1  Battery. 

12 

Connect the battery positive terminal. 

13 

Connect the battery negative terminal. 

Alternate Load Test 

If HRD test equipment is not available, test the battery as follows: 

1 

Read and obey the safety precautions for working with batteries, refer to 2  Safety Precautions. 

2 

Ensure the state of the battery is at least 65% charged. Refer to 3.3 

Hydrometer Test. 

3 

Connect a voltmeter (1) between the battery terminals.

4 

Turn the headlights on to high-beam for 10 seconds to 
remove any surface charge from the battery. 

5 

Remove fuses EB11 and EB12 from the engine 
compartment fuse and relay housing. This prevents 
vehicle ignition and fuel injection while cranking the 
engine. 

6 

Crank the engine and read the voltmeter. At 
temperatures above 5°C, the voltage of a fully charged 
battery should not fall below 9.6 V. 

N O T E  

•  If the battery and engine temperatures are 

below 5

°C, the voltage may fall to 9 V. 

•  Try to avoid activating the starter motor 

continuously for more than 30 seconds. If 
activating the starter motor for 30 seconds, 
allow the starter motor to cool for 3 minutes. 

7 

Replace the battery if a cell gasses excessively or 
overheats or if the voltage falls away quickly. 

Figure 6D1-3 – 6 

3.5 

Battery Current Draw Test 

The following test determines if excess current is being drawn from the battery whilst the vehicle has all accessories 
turned off. Excess current draw will cause the battery to go flat if the vehicle is not started for an extended period. 

Test Preparation 

1 

Read and obey the safety precautions for working with batteries, refer to 2  Safety Precautions. 

2 

If the battery is flat, temporarily install a good battery for the duration of the test. 

3 

Ensure the vehicle starts and the accessories operate normally. 

4 

Ensure the theft deterrent system operates normally. Refer to 11A Immobiliser. 

5 

Open all the side windows for access purposes. 

6 

Switch the ignition off. 

7 

Check that all interior illumination is off, including any compartment lighting. 

8 

Close all doors.