Midtronics high-frequency testers (with the LCD screen & 5 buttons down the right side) are the industry standard for battery testers, and most dealerships (of most makes) are required to use them for
warranty returns. I have this model with the built-in printer, but no alternator diagnostics.
https://www.midtronics.com/testers/mdx-p300/Load testing is not recommended or accepted by Ford.
Before buying a craptasmic battery or other common part, check for
coupons & service offers from Ford.
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This battery tester is not a multimeter, and even the best DMM can't do what the tester does. But if you need a decent meter, consider this one, or one with most of its features:
For more info, see
http://www.batteryfaq.org/ 
