Tip & How-To about Hammering

How to use a voltage or multi meter.

You can buy a reliable, two probe voltage meter at most building supply stores for around $30. They typically have two testing probes and a dial to select the function. The four major functions are AC voltage, (a V with a wiggly line), DC voltage (a V with a straight line), resistance or continuity (the symbol omega), and amps(A). To use the meter you decide what value you are testing for and estimate what range the result would be in. For example, testing a receptacle, you would use AC Volts on a 200 range, expecting a 120 volt reading. For continuity or resistance, select a mid range to start with. Hold one probe to each side of the circuit or item to be tested. If the reading is infinite then there is no internal connection between the parts tested. If the reading is zero then there is a connection or a short between the parts being tested. For example, if you put the probes on the terminal screws of a switch, one position would give you a zero reading, and flip the switch and you would get an infinite reading. For a light bulb an infinite reading means it is burned out, a zero or close to it reading means the lamp is good.
You would use the DC Voltage function to check circuits in your car, or to check batteries. The car is 12volts DC and a battery is 1.5 volts DC.

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1999 cadillac seville wiring diagram

Check wiring with a test light or volt meter. switch lights to low beam, connect volt meter N probe to a good ground then probe the light socket for the low beam power cable, should show battery voltage, now switch to high beam and test for battery voltage if ok remove the grounded meter probe and probe the cable in the socket that you have not tested this is the ground cable, battery voltage should show if ground cable is ok. If no voltage repair cable ,If voltage present check filament on bulb high beam perhaps the new bulb is faulty.

Jul 10, 2014 | 1999 Cadillac Seville

2 Answers

how test circuit diode schottky

Take your digital volt meter. Place meter on the diod setting. Place your probes on each leg. You should read .7 to .2 in the forward position and infinity or high megs in the reverse position. You'll need the data sheet to find out spec.

May 30, 2014 | Electronics - Others

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92 fxdc not charging

To test your charging system, you need a fully charged battery in the bike and a digital volt ohm meter. Set your meter's function selector switch to DC VOLTS with a range of at least 20 volts. Connect the meter's red lead to the positive battery post and the black lead to the negative battery post. Start the engine and bring it to a high idle. After a minute or so, the meter should read between 14.5 and 15.0 volts. If not, proceed to the the alternator test.

To test the alternator, put your meter's function selector switch to AC VOLTS with a range of at least 50 volts. Find the plug where the regulator plugs into the engine case on left lower front of the engine. Unplug the plug from the regulator and look into the engine side of the plug. You'll see two metal contacts. This is where you are going to put the probes, one into each metal contact, to check the output of the alternator. Put both meter probes in the contacts, one probe into each one. It makes no difference in this test which goes where. Do not allow the probes to touch each other or the engine case. Start the engine and bring it to a high idle. Insert the probes into the contacts and read the voltage. You should have at least 30 volts or more.

If you do not have at least 30 volts output from the alternator, your stator is bad and needs replacing. If you do have at least 30 volts out of your alternator but less than 14.5 volts at the battery, your regulator is probably bad. Make sure the regulator is grounded properly. I usually put one of the star type lock washers between the body of the regulator and the frame on both bolts that hold the regulator on.

Good Luck

Jul 07, 2011 | Harley Davidson FXDL Dyna Low Rider...

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Ge microwave mod. #JVM1851BH06. i ohmed the capicitor 2 meg ohm and increased to 11 meg ohm. I also measured the diode which i believe branches off one leg of capacitor it shows open resistance O.L. both directions and on diode tester. In the auto industry nothing has 2 meg plus of resistance and a diode should read low resistance in one direction. Is it safe to say both components are bad?

I'd say your diode is bad but your capacitor may be good. You need to test it further - as described below.

In order to get reliable measurements to make a determination about the condition of the components, each should have at least one lead removed from the circuit. If not, your meter will read the through the rest of the circuit - and not be limited to the diode or capacitor under test.

To check a diode: Set the meter to to the lowest scale (Rx1) and touch black (-) probe to the cathode of the diode (the end with a band around the diode body) and the red (+) to the anode lead to reverse bias the diode. The meter should indicate "OL" or high resistance. Reverse the meter probes so that RED (+) is on the cathode lead and black (-) is on the anode to forward bias the diode. The meter should read a very low resistance - approaching 0 ohms. Diodes should conduct in one direction only - and the other is should look "open" If it conducts or is open in both directions, it is defective. Zener diodes can be checked with an ohm meter, but need a variable voltage supply and are required to be in a circuit (instead of out of circuit like a standard diode) for accurate testing. A link to zener diode testing here.

To check a capacitor: Set the meter to the lowest scale (Rx1) and touch probes to capacitor leads. The meter should indicate "OL" or high resistance and show steadily decreasing resistance before increasing to OL or high resistance again. Swap probes from the meter on the capacitor leads and "OL or high resistance indication should change to an even lower amount of resistance thas before before returning to "OL" or high resistance indication. These are test result characteristics of a good capacitor under test.

I hope this helps & good luck! Please rate my reply - thanks!

Jan 27, 2011 | GE Profile Spacemaker Over-the-Range...

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dc9099 wont charge in charger. need new charger would like to know which one to buy, the one i have is from usa and is not compatible to our electricity

Firstly I would suggest that you check whether the problem is really with the charger or the Dc9099 Battery itself. All rechargeable batteries deteriorate over time, especially if they are left fully discharged for a long time or are frequently left on charge for extended periods.
If you have a spare battery try charging that.
You can test the charger itself with a digital multimeter (electrical test meter). 1) plug in your battery charger to mains supply and switch on. 2) Set the scale on the test meter to 200 volts DC Voltage (V--) 3) Insert the test meter probe wires in the sockets on the meter marked "Com" (black) and "V/Ohm (red) 4) Touch the other ends of the probes onto the metal contacts on the charger. It doesn't matter which way round you do it
If the voltage reads in the region 20-25V (will be either + or - depending on which way round you place the probes on the contacts )the charger is probably working okay.
If you have a battery charger that is for US Voltage (110)volts you can buy a 240V-110V step down converter quite cheaply here. http://cpc.farnell.com/_/mw2p-045/45w-230-110v-ac-ac-adaptor/dp/PW00942?crosssellid=PW00942&crosssell=true&in_merch=true&

Jan 24, 2011 | Dewalt DC9099 18v Battery

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