Chuck S

My battery died in the church parking lot at my daughter's wedding rehearsal. Got a push start and drove home. Voltage was good the next morning. No start again. The resistance test meter showed too much voltage drop. New battery fixed it. Sometimes batteries just die.

-- Chuck

windhund116

I think he meant to place a known ohms amount resistor FROM the (+) terminal of battery and high tension (+) wire. And measure DC voltage drop. Say, you use a 1-ohm resistor... and the DC voltage you read is 1.2VDC. Then, the current drop (by Ohm's Law):

Current (amps) = (Voltage drop) divided by (resistance) = (1.2VDC) X (1-ohm) = 1.2 amps. A huge current drain.

If you use a recent made, good DVM (like a Fluke) --- it'll have a fuse built in, so you can't run 10-amps through it and fry the meter. Drain measurements should be done with engine OFF. You are measuring for excessive current draw ---> Engine off. Car standing, no key in ignition.

If you use a test light, you look for changes in the intensity of the light --- as you pull fuses, one-by-one. If the light gets brighter with one fuse ---- check the circuit that the fuse is associated with, for shorts. Or bad accessory attached.

Car Analogy

Exactly. Good improvement on describing how to do this test.

Except note if the test light is hooked up in line between the battery and the cable you removed from battery, then the light will get DIMMER when you pull the fuse for the leaking circuit...

brokens2000

Sorry to revive this thread but would just like to let others know what I came up with as a solution- First off I found that the jumper I put on the clutch safety switch was grounding out on a very minimal degree- went ahead and bought a new switch & the draw went away. Second replaced the junko Napa battery with an Odyssey- have been good as new since.