fuse blows when probing the wire

why would a fuse blow when probing the wire.

hmmm lets think about this question...... bad connection, you probed too deep and grounded connection, probed into another connection. Maybe your probe is broke.

You better know what you are probing. Better be safe than sorry, use a digital mulitimeter. Use this piece of equipment and it will answer your question WHY.

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Be careful whose advice you buy, but be patient with those who supply it.

the wire was the main wire for the trunk and gas
so the probe light is not safe? If you have to probe wires to install an alarm how can you if you dont know what wire is what in the car. the alarm manual says probe the wire or wires and find a wire that shows a 12v+. you have to probe by trial and error.

A simple test light should not be used to probe wires.  It does not offer much resistance, and can draw much more current through a circuit, frying computers and the like.  Use a multimeter, or a logic probe. 

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My ex once told me I have a perfect face for radio.

the probe light came with the car alarm in the box and the manual says to probe the wire or wires that must mean to test any wire.
how does the multimeter is it safer then the probe light?

Read through here and you will understand why.

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Be careful whose advice you buy, but be patient with those who supply it.

so the DMM works the same as a probe light but does not send out current to the wire and blow a fuse?

When you're testing for voltage, you're actually creating a parallel circuit with the equipment you're checking.  Think about it.  Now both the gear you're testing, and the light have to draw power.  When you create a parallel circuit, your total resistance decreases- plain and simple.  As resistance decreases, current increases, and your fuse blows. 

Now most multimeters (and logic probes) have internal resistances into the Mohms (millions), so the decrease in total resistance and increase in total current is negligible.  However, if you put a test light in the equation, which has maybe- 20 ohms (just picking a number), it will have a much greater effect on the operation of the applicable circuit.

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My ex once told me I have a perfect face for radio.

im trying to test for the door locks for the alarm
the unlock wire is in black plug in kick panel and there is more then one black wire there I dont want to blow a fuse with the probe light so I will try the dmm.

How can I use the DMM to find the unlock wire if I unlock the door I would see the DMM change?

Yes, you'll see a change.  You didn't say what year, make and model vehicle you have.  Probably the most common setup uses negative triggers, so you'll have 12v at rest, and it'll drop off when you hit the locks.  Some vehicles, however, like Chryslers use one wire for door locks, and you trigger the ground through a set value resistor for lock, and another value for unlock.

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My ex once told me I have a perfect face for radio.

get yourself a digital multimeter it will save you the headaches and tears.much safer too.

I have a voltimeter but dont know how to really use it.
im use to the probe light. its a 92 mazda 929
I want to probe the lock wires with the voltimeter how to use it

Set the meter to voltage, touch black to a ground (cigarette lighter rim), touch red to your suspect wire.

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My ex once told me I have a perfect face for radio.

Patience is a virtue geepherder, I appluad you.

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Check all advice given with a meter

I have trhe actron cp7672 model
DMM
Set it on DCV and what number to test wires for alarm setup. there is 20 200m ect on that model.

You want to use the level above what you expect to measure.  That would be the 20 volt setting.

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My ex once told me I have a perfect face for radio.

ok I set it on DCV 20 and just probe the wire. Now the the wiring chart says the alarm locks are a negative type. so I probe the wire using the red lead and what should I see on the multimeter to know its correct?

If it shows 12v normally, it'll drop off to 0 when you press the button.  If it doesn't show 12v at rest, set your meter to resistance (a low setting), and measure resistance to ground.  When you press the button, you'll have a low resistance reading.

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My ex once told me I have a perfect face for radio.

I checked the alarm wiring chart and it shows the doors are negative. so with the DMM all I just have to do is put the black lead to ground and red to the wire im testing. is that for any wires im testing? unlike the probe light to test a negative you have to clip the red end to 12v and then probe. and to test a postive I clip to a ground

It sounds like you've got it.

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My ex once told me I have a perfect face for radio.

ok so thats how you test the wires
Let me double check If the wire in the car is postive or negative I always but the black lead from tbe DMM to the Car's ground and the red lead from the DMM to any wire?
I hope I got it correct, I will go and test out the locks

What about testing for a postive Do I still put black to ground and the red to the wire does it matter if its a postive or negative?

Yes, that's correct.

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My ex once told me I have a perfect face for radio.

I probed the wire but its the same when its lock and unlock
it shows 12v+ you said something about setting it to a low setting how can I do that my meter goes only to 20.

If nothing changes when you press a button, you're testing the wrong wire.  Keep looking.

I said use a low setting if you're testing resistance to ground.  If you're measuring voltage use the 20v setting.

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My ex once told me I have a perfect face for radio.

The wire is the correct one
its a negative door lock system.

If you can't verify with a meter that's the wire you need, can you explain how you know it is the correct one?

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My ex once told me I have a perfect face for radio.

the wiring chart says relay above pedal
and thats the only color in the area to be GRAY/BLACK.
I will double check on it later

Don't take any wiring charts for granted (wiring colors are often wrong).  I use them as a starting point, then verify my wires with a meter or logic probe.  You're probably in the right area, but if you don't see a different reading when you press the buttons, you're on the wrong wire.  You maybe on the wrong side of the relay's coil.

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My ex once told me I have a perfect face for radio.

I will retry it again something is not correct like you side. I do get 12v on the DMM.

I will retry it again something is not correct like you said. I do get 12v on the DMM.

i am a newbie here, but i will take a stab at this question. here it goes. if i remember correctly the 929 and protegee use whats called a resistor type door locking. in orhter words the DLM looks for diffrent values in the line. a single line. now depending on the the resistance of that line, that tells the DLM weather to lock or un-lock. but don't hold me to that. i could be wrong.

He's probably right.  Is this a one-wire system?  If so, it's probably just like a Chrysler.  You'll need to pulse a ground to the wire through resistors and relays.

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My ex once told me I have a perfect face for radio.

The wiring chart fir the alarm says its a type b negative system so there is a wire for the lock and unlock.

Yes, I show two separate wires: lock(grey/black), unlock(blue/white).

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My ex once told me I have a perfect face for radio.

I will test the connection again.

I tested the wire again and its the same thing when you lock and unlock the wire.
im getting 12v.
now If I use a probe light Its a negative system so I would have to connect the red clip to 12v source then probe the lock wires.

Hey I don't want to thrash on you but it sounds like you don't know what you are doing. I would recommend taking it to a shop and have a professional look at what you are getting into. I wouldn't recommend installing alarms, remote starts, keyless entry systems unless you have the knowledge of car electronics. If this is your first you may try finding someone to help you that has done it many times before rather than a shop. It would save on time and money to find some professional help.

why are you talking thrash every car is different.
why would I take it to the shop when I can do it myself.
the other cars I worked on was cool but this one is a bit different.

You keep proving to us your wiring info, as well as mine is incorrect.  Try another wire.  You can start checking inside the kick panel, or you can back probe the switch and check for wire colors there.

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My ex once told me I have a perfect face for radio.

I tested the wires and both the lock and unlock has voltage at rest. when I tested the unlock wire I got a reading on the DMM even if it was not 12volt and once I hit the unlock button the volt dropped and came back up. then I hit the lock button with the dmm still on the unlock wire the voltage did not get affected. I guess I found the wires thanks