Title: Module 5: Battery Maintenance & Replacement - Activity
Course: ASE A6 Battery Service > Section: Module 5: Battery Maintenance & Replacement

Q: When removing a battery from a vehicle, which cable must be disconnected first?
- Positive cable
- Negative cable
- Either cable — the order does not matter
- The smaller-gauge cable
A: Negative cable

Q: When installing a battery in a vehicle, which cable must be connected first?
- Negative cable
- Either cable — the order does not matter
- Positive cable
- The cable closest to the fender
A: Positive cable

Q: White powdery buildup on a battery post is most likely:
- Copper sulfate from the cable clamp reacting with acid vapor
- Lead sulfate from acid vapor reacting with the lead post
- Dried baking soda from a previous cleaning
- Calcium deposits from hard water in the electrolyte
A: Lead sulfate from acid vapor reacting with the lead post

Q: Green powdery buildup on a battery cable clamp is most likely:
- Lead sulfate from the battery post
- Oxidized solder from the cable connection
- Copper sulfate from acid vapor reacting with the copper in the clamp
- Mold growth caused by moisture in the engine bay
A: Copper sulfate from acid vapor reacting with the copper in the clamp

Q: A flooded battery has the electrolyte level below the tops of the plates and needs to be charged. What is the correct procedure?
- Charge the battery first, then add distilled water to the full fill ring
- Add distilled water to just above the plates, charge, then top off to the fill ring after cooling
- Add tap water to the full fill ring, then charge
- Replace the battery — exposed plates cannot be recovered
A: Add distilled water to just above the plates, charge, then top off to the fill ring after cooling

Q: What is the primary purpose of a battery hold-down?
- To ground the battery case to the vehicle chassis
- To prevent the battery from vibrating during driving
- To compress the plates for better chemical contact
- To seal the battery top to the case
A: To prevent the battery from vibrating during driving

Q: Which of the following vehicles would most likely require battery registration with a scan tool after battery replacement?
- 2012 Honda Civic with a flooded battery
- 2015 Toyota Camry with a flooded battery
- 2019 BMW 330i with an AGM battery
- 2008 Chevrolet Silverado with a flooded battery
A: 2019 BMW 330i with an AGM battery

Q: The maximum acceptable voltage drop across the entire positive battery cable (battery post to starter terminal) during cranking is:
- 0.1V
- 0.3V
- 0.5V
- 1.0V
A: 0.5V

Q: The maximum acceptable voltage drop across the entire negative battery cable (battery post to engine block) during cranking is:
- 0.1V
- 0.3V
- 0.5V
- 1.0V
A: 0.3V

Q: During a visual inspection, a battery shows bulging or swollen sides. This most likely indicates:
- The hold-down is too tight
- The battery is undercharged
- Overcharging, overheating, or frozen electrolyte
- Normal expansion from a full charge
A: Overcharging, overheating, or frozen electrolyte

Q: Describe the complete terminal cleaning procedure in the correct order. Include the cable disconnection and reconnection sequence, the cleaning solution, the correct use of a battery terminal brush, and the final protection step.
Feedback: (1) Disconnect the negative cable first, then the positive cable. (2) Mix a baking soda solution (1 tablespoon per cup of warm water). (3) Apply the solution to the terminals and cable ends — fizzing indicates acid is being neutralized. (4) Scrub with a battery terminal brush — use the internal cone for the inside of the cable clamp and the external ring for the battery post. (5) Rinse with clean water. (6) Dry thoroughly and inspect — both surfaces should be shiny bare metal. (7) Reconnect the positive cable first, then the negative cable. (8) Apply anti-corrosion spray or install felt washers. (1 point for correct disconnect order, 1 point for cleaning solution, 1 point for correct brush use, 1 point for rinse/dry/inspect, 1 point for correct reconnect order, 1 point for anti-corrosion protection)

Q: A technician performs voltage drop tests on a vehicle's positive battery cable during cranking and gets the following readings: - Across the entire positive cable (battery post to starter terminal): 0.8V - Battery post to positive cable clamp: 0.6V - Positive cable clamp to starter terminal: 0.2V Is there a problem? If so, where is it located, and what should the technician do to correct it?
Feedback: Yes — the positive cable has excessive voltage drop (0.8V exceeds the 0.5V maximum). The majority of the drop (0.6V) is occurring between the battery post and the cable clamp, which exceeds the 0.1V maximum for a single connection point. This indicates heavy corrosion or a poor connection at the positive battery terminal. The technician should remove the cable clamp, clean both the post and the inside of the clamp with a battery terminal brush, and retest. If the voltage drop remains high after cleaning, the cable clamp should be replaced. (1 point for identifying excessive voltage drop, 1 point for locating the problem at the post-to-clamp connection, 1 point for comparing readings to specifications, 1 point for the correct service recommendation, 2 points for complete explanation)

Q: A technician performs voltage drop tests on a vehicle's negative battery cable during cranking and gets the following readings: - Across the entire negative cable (battery post to engine block): 0.5V - Battery post to negative cable clamp: 0.08V - Negative cable clamp to engine block ground point: 0.42V Is there a problem? If so, where is it located, and what should the technician do to correct it?
Feedback: Yes — the negative cable has excessive voltage drop (0.5V exceeds the 0.3V maximum for the negative cable). The post-to-clamp connection is fine (0.08V is under the 0.1V maximum), but the drop from the cable clamp to the engine block ground point (0.42V) far exceeds the 0.1V maximum for a single connection. This indicates either a damaged cable (broken strands, acid wicking, corrosion under insulation) or a poor ground connection at the engine block. The technician should first clean the ground connection at the engine block. If the voltage drop remains high after cleaning, the negative cable should be replaced. (2 points for identifying the problem location in the cable or ground connection, 2 points for comparing readings to specifications, 2 points for the correct service recommendation)

Q: A 2019 BMW 330i has its battery replaced with the correct AGM battery and the cables are reconnected properly. A 2015 Toyota Camry also has its battery replaced with the correct flooded battery. Compare the two vehicles: is battery registration required for each one, and why or why not?
Feedback: The BMW requires battery registration. BMW vehicles (2002 and newer) have an Intelligent Battery Sensor (IBS) and Battery Management System. The technician must connect a scan tool to the OBD-II port, navigate to the battery registration function, and enter the new battery's information (part number, capacity, date code). Without registration, the BMS will continue using the old battery's degraded charging strategy, potentially overcharging the new battery and reducing its life. The Toyota does not require battery registration. Most Toyota vehicles of this era use a standard fixed-voltage charging system that does not adapt based on battery age. The technician should install the correct battery, connect cables in the proper order (positive first), and verify proper operation. A memory saver is still recommended to preserve radio presets and learned idle values, but no scan tool registration is needed. (1 point for correct BMW answer, 1 point for BMW explanation, 1 point for correct Toyota answer, 1 point for Toyota explanation, 1 point for consequence of skipping BMW registration, 1 point for noting Toyota memory saver recommendation)

Q: A 2020 Ford F-150 with a start-stop system has a dead AGM battery. The customer wants to save money by installing a less expensive flooded battery instead, and the technician registers the new battery type in the Battery Management System. Explain whether this is acceptable and why.
Feedback: This is not acceptable even with correct registration. A start-stop system requires an AGM battery because of the frequent deep cycling demands — the engine stops and restarts at every red light, traffic slowdown, or idle period. A flooded battery cannot handle this repeated deep cycling and will fail prematurely. The BMS may accept the registration of a different battery type, but the flooded battery will not physically withstand the operating demands placed on it by the start-stop system. The customer must install an AGM battery of the correct group size and CCA rating. The short-term savings on a cheaper battery will be lost when the flooded battery fails early and potentially leaves the customer stranded. (2 points for correctly identifying this as unacceptable, 2 points for explaining why AGM is required for start-stop cycling demands, 2 points for explaining that registration does not overcome the physical limitations of the battery type)