FOXWELL BT705Plus Car Battery Tester 12V/24V Load & Alternator Tester — 2.8" Colour Display, Long Leads

The FOXWELL BT705Plus is a handheld automotive tester that quickly assesses 12V batteries and 12V/24V charging and cranking systems to reveal weak batteries, starter issues, and alternator problems.

Compact and engineered for both professionals and DIYers, the BT705Plus blends faster processing and refined algorithms to return more reliable results, even on low-voltage or nearly depleted batteries. Its 2.8" color display, extended test leads, and multi-mode diagnostics let you run battery health checks, cranking assessments, and charging inspections without guesswork. The tool supports flooded, AGM, spiral-wound, and GEL battery chemistries (not compatible with lithium) and works across passenger cars, trucks, RVs, boats, and heavy equipment.

How does the BT705Plus identify a weak battery?

The BT705Plus runs a targeted battery test that calculates state of health (SOH) and state of charge (SOC) using measured voltage and internal resistance under load. It compares results against the battery's rated CCA to classify the battery’s condition and recommend actions.

• Enter the battery's rated CCA from the label for accurate comparison
• Displays SOH and SOC and a clear pass/fail-style status
• Works with flooded, AGM, spiral, and GEL types (no lithium support)
• Larger readings available even for low-voltage or nearly dead batteries

Can it test starting performance and measure cranking?

Yes—the BT705Plus performs cranking tests that record cranking voltage and cranking time to help pinpoint starter or battery-related starting problems. Run the test while cranking the engine to capture real-world starting behavior.

• Measures cranking voltage and duration to reveal weak starts
• Use long 5.9 ft cables to test from the driver’s seat safely
• Ideal for detecting intermittent starting issues before a roadside failure

How does the device check alternator and charging systems?

The charging test inspects charging voltage and monitors alternator ripple to surface regulator or diode faults and unstable charging. Results show whether the charging system maintains correct voltage and whether ripple levels are within acceptable limits.

• Performs 12V and 24V charging system checks on many vehicle types
• Reports charging voltage and ripple to indicate alternator health
• Recommends tests be done with accessories off and ignition OFF for accuracy

What makes the BT705Plus easier to use than basic testers?

The unit’s faster processor and tuned algorithms produce results up to 30% quicker than its predecessor while the large color screen shows multi-value diagnostics at a glance. Rugged, high-conductivity clamps and long cables let one person safely perform all tests without assistance.

• Bright 2.8" color LCD for clear outdoor and indoor visibility
• Extra-long 5.9 ft cables permit in-seat testing of cranking and charging
• Storage box included for safe transport and workshop organization
• GRS-certified manufacturing for responsible production practices

Who is this for? Mechanics, fleet managers, and hands-on vehicle owners who want a professional-grade, portable diagnostics tool that covers battery health, cranking performance, and charging system integrity. It’s particularly useful for workshops, roadside technicians, and anyone who wants to detect battery or alternator problems early—reducing unexpected breakdowns and unnecessary replacements. Note: the BT705Plus diagnoses systems but does not charge batteries and is not an OBD2 code reader; always enter the battery’s rated CCA and follow test setup steps for consistent results.