Re: Winnebago vectra front lights
If a light will not light, than one of the following is likely true:
1) The bulb is broken or the socket has a bad connection. Unlikely in your case since all don't work
2) The fuze is blown. Moderate probability, look for the fuze or fuzes which power the failing lights and test them.
3) It's not getting power. Check the cable which is supposed to provide the power to the light to ensure that it is plugged in. Wiggle any connections, particularly those which are connected to all the lights which are failing.
4) It does not have a good ground connection. This is the most likely in your case. Look for a ground wire connected to all the bulbs, which should be connected to the frame or chassis ground. Make sure the connection is correct and good.
5) If all else fails, use a voltmeter or test light to trace the wiring to find the fault.