headlight issue - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

94porkchop · 06-02-2008, 01:32 PM

low beam doesnt work-high beam does.only on the driver side.i switched bulbs.it's not a bulb issue.any ideas?

brokeAs240sx · 06-02-2008, 03:09 PM

first things first,

Take a multimeter to the headlight plug.

1 wire = ground
1 wire = low beam
1 wire = high beam

See if you are getting the correct voltages to each wire when headlight switch is OFF, Low Beam, and High Beam. I'm guessing Off & High Beam will give you the right readings (this will help if you don't have a wiring diagram, since you can infer that the remaining wire is low beam).

In any case, from there, if there is voltage, obviously, something is wrong w/ the headlight. If there is no voltage, you gotta start back tracking/tracing the wire -> fuse/relay box below the intake filter -> interior fuse panel -> switch.

You could also start from the headlight switch side, which is a fairly common item to fail (the contacts no longer touch correctly).

06-02-2008, 01:32 PM	#1
94porkchop Zilvia Member Join Date: Apr 2004 Location: nj Posts: 218 Trader Rating: (1) Feedback Score: 1 reviews	headlight issue low beam doesnt work-high beam does.only on the driver side.i switched bulbs.it's not a bulb issue.any ideas?

06-02-2008, 03:09 PM	#2
brokeAs240sx Nissanaholic! Join Date: May 2004 Location: Southern California Posts: 1,917 Trader Rating: (40) Feedback Score: 40 reviews	first things first, Take a multimeter to the headlight plug. 1 wire = ground 1 wire = low beam 1 wire = high beam See if you are getting the correct voltages to each wire when headlight switch is OFF, Low Beam, and High Beam. I'm guessing Off & High Beam will give you the right readings (this will help if you don't have a wiring diagram, since you can infer that the remaining wire is low beam). In any case, from there, if there is voltage, obviously, something is wrong w/ the headlight. If there is no voltage, you gotta start back tracking/tracing the wire -> fuse/relay box below the intake filter -> interior fuse panel -> switch. You could also start from the headlight switch side, which is a fairly common item to fail (the contacts no longer touch correctly). __________________ bew bews!