I have a 9004 Headlamp in my car. I want to test the female electrical connector to the lamp. I know the connector has a high beam, low beam, & negative. I know which ones they are. Please tell me exactly how to test it with a multimeter. thanks.
Turn the multimeter to DC volts, to the 12 volt range if it isn’t autoranging. Then touch the probes to the connector. You should get a reading of approximately 12 volts.
Connect the black (negative lead) of the multimeter to a good ground on the frame or to the negative battery terminal. Set the multimeter on the voltage scale for 20 volts. Turn on the headlights and select low beam with the dimmer switch. The reading should be around 12.4 volts or so. Then select the high beam with the dimmer switch. The voltage at the low beam connection should be 0 volts and at the high beam connection should be 12.4 volts. If you get voltage at each of these terminals, put the black lead into the negative connection and repeat the test. You should get the same results. If not, the headlight ground is bad. You have then tested all the connections on the connector.
when i do this will it be safe or will there be sparks? i do this with the car off, right?
No sparks, car on or off doesn’t matter. There isn’t enough power at the headlight socket to hurt you. Well maybe if you stick your tongue in the socket.
thanks Xebadaih. i’ll try it tomorrow. tongue in mouth. Rig
Hey Rig ! Sorry I wasn’t around but it appears you’ve been getting some solid advice. Make sure that ground is solid. U can do that by attaching your ground to something like the negative terminal (black cable clamp) on the battery.