How To Check Fuses

Using a test light(1) connected to a GOOD ground, probe both sides of the fuse. Key must be on. It is a good idea to check all fuses in all fuse blocks when a blown fuse is suspected. Some of todays vehicles use many fuses and several fuse blocks to power a particular circuit / system.

The fuse is the most common method of an automotive wiring circuit protection. Whenever there is an excessive amount of current flowing through a circuit the fusible element will melt and create an open or incomplete circuit. Fuses are a one time protection device and must be replaced each time the circuit is overloaded.

How to test vehicle electrical fuses with a test light
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Fuse Examples And Ratings Color Chart


Question: I have a pontiac grandam 2003 and it wont start we replaced battery,checked starter,tryed w/booster cables still wont start not sure what it is ?
 Answer: A battery can be so far gone that a jump will not help. Check for power at the purple wire at the starter when cranking. It should be hot. Is the theft or security light on?

I have an 04 grand am gt and some of the fuses in fuse box under hood have no power such as ignition module. is this normal
 That depends if you are checking the fuses with the key in the on or off position. Some fuses will have power with the key off, most with the key on, some only when a certain circuit is being used- such as headlights. If the car does not have any starting or running problems, I would not worry about your findings.

I have a 1997 Oldsmobile Aurora the car drives normal until the check engine light comes on and the car feels like something is stuck, the idle goes high and I try to step on the gas it strains and looks as if it will over heat. Do u have a clue what could b the problem.


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