This procedure tests the battery state of charge and health using a battery tester to determine if the battery requires charging or replacement.

Warnings

Tools required

Preparation

1. Park vehicle on level surface and apply parking brake
2. Turn off engine and all electrical accessories (lights, radio, climate control)
3. Allow battery to rest for at least 1 hour after engine shutdown for accurate voltage reading
4. Open hood and locate battery in engine compartment on passenger side

Procedure

1. 1

   Inspect battery condition
   Visually inspect the battery case for cracks, bulges, or leaks. Check battery terminals and cables for corrosion, damage, or looseness. Look for acid residue or white/green powder around terminals. Inspect battery hold-down bracket for tightness. If severe corrosion or damage is present, proceed with caution.
2. 2

   Clean battery terminals if needed
   If corrosion is present on terminals, use wire brush or battery terminal cleaner to remove buildup from both positive and negative terminals and cable clamps. This ensures accurate test results. Clean until bright metal is visible on contact surfaces.
   Torque spec

   Battery Terminal Bolts8 Nm (6 lb-ft)
3. 3

   Verify terminal connections
   Check that both battery terminal bolts are properly tightened to 8.0 Nm (6.0 lb-ft). Terminals should not be able to twist or move on battery posts. Loose connections will cause inaccurate test results and vehicle electrical problems.
   Torque spec

   Battery Terminal Bolts8 Nm (6 lb-ft)
4. 4

   Perform open circuit voltage test
   Using the battery tester or multimeter, measure the voltage across battery terminals with engine off and all accessories off. Connect positive lead to positive terminal and negative lead to negative terminal. Record voltage reading. A fully charged 12-volt battery should read 12.6V or higher. 12.4V indicates 75% charge, 12.2V indicates 50% charge, and below 12.0V indicates discharged battery requiring charge before further testing.
5. 5

   Connect battery tester
   Connect the battery tester leads to the battery terminals, ensuring proper polarity (red to positive, black to negative). Input battery specifications into tester when prompted: 12V system, battery CCA rating (typically 650-750 CCA for F-150 3.5L EcoBoost, check label on battery). Follow tester manufacturer's instructions for test setup.
6. 6

   Perform battery load test
   Execute the load test function on the battery tester. The tester will apply a load equivalent to half the CCA rating for 15 seconds while monitoring voltage. During the test, battery voltage should not drop below 9.6V at 70°F (higher minimum at warmer temperatures, lower at colder). Record the test results including voltage under load and internal resistance or conductance reading.
   ⚠Battery may become warm during load test. This is normal but discontinue if battery becomes hot or emits odor.
7. 7

   Interpret test results
   Review battery tester display for pass/fail indication. PASS indicates battery is good and holding charge. CHARGE indicates battery is discharged but serviceable and needs charging. REPLACE indicates battery has failed and cannot hold adequate charge. Note that most modern testers also provide state of health (SOH) percentage - below 80% typically indicates replacement is needed. Document CCA test result compared to rated CCA.
8. 8

   Test charging system if battery is good
   If battery tests good but vehicle has been experiencing electrical issues, perform a quick alternator output check. Start engine and measure voltage at battery terminals with engine running at idle. Voltage should be 13.8-14.4V. If below 13.5V or above 15.0V, charging system requires further diagnosis.

Reassembly

1. No disassembly required for this procedure
2. If terminals were loosened during cleaning, retorque Battery Terminal Bolts to 8.0 Nm (6.0 lb-ft)
3. Clean any tools that contacted battery acid with water and baking soda solution

Verification

• Confirm battery test results are documented with voltage readings and pass/fail status
• If battery tested good, verify all electrical accessories function normally
• If battery failed test, recommend replacement with equivalent or higher CCA rating battery
• If battery required charging, retest after full charge cycle to confirm battery health
• Verify battery terminals are clean, tight, and corrosion-free before closing hood

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