One Head Light working


samson

GT Owner
Nov 3, 2014
51
Harrogate TN
Hi guys.
Needing some advice on tracing down my headlight issue on my 05 GT. Passenger side Just stopped working. Changed the bulb and didn’t help.

Swapped the relays around and no difference.

I am guessing the switch or the fuse box area under passenger dashboard. What’s my best way of testing or fixing it from here?
 

nota4re

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Feb 15, 2006
4,176
Use a voltmeter with negative lead connected to the battery and test for 12V at the headlamp and work your way backwards. It is possible that you DO have 12v at the bulb socket and if so, then you have a ground issue. Then test at the relay - Dark green with orange stripe is the "trigger" wire coming from the SJB. Please note that the left and right headlight have their own individual fuse. The right headlamp is 25A fuse in position F1.18, and the Left headlamp is fuse F1.17. (I would check F1.18 first and cross your fingers.)
 
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samson

GT Owner
Nov 3, 2014
51
Harrogate TN
Use a voltmeter with negative lead connected to the battery and test for 12V at the headlamp and work your way backwards. It is possible that you DO have 12v at the bulb socket and if so, then you have a ground issue. Then test at the relay - Dark green with orange stripe is the "trigger" wire coming from the SJB. Please note that the left and right headlight have their own individual fuse. The right headlamp is 25A fuse in position F1.18, and the Left headlamp is fuse F1.17. (I would check F1.18 first and cross your fingers.)



Great help. I didn’t realize there was a fuse and hope that’s the trick. I will be home to check in a few days. Fingers crossed.