Electrical - Tips

You can use a heavy gage of wire to make a connector pin jumper lead. Cut a short length of wire, place the wire over the male pin in the connector and then place the meter probe into the other end of the wire that is now hanging from the connector. This allows you to leave the meter connected to a pin and still use your hands for other things.
 
You can also make a lead to use on the female side of the connector the same way - just strip back a portion of one end and 'tin it' (solder the end of the wire). Making and using these leads also help in preventing you from shorting something out by inadvertently touching the probe to two or more pins.


The safety pins shown here are an easy way to get a multimeter lead inside a connector - just make sure you don't cross them, and that when you expect voltage to be on that particular wire you have the ignition on and the switch in the right position.
 
If you absolutly think you have to you can use a straight pin to measure voltage or ohms on a wire where you cannot for one reason or another disconnect the circuit to check it. Insert the straight pin into the insulation, and place your meter probe on it to make your reading. Remove the straight pin when you are done and make sure you put a dab of silicone over the pin hole(s) to seal the wire or you will allow corrosion to start building inside the wire.