Under hood light going haywire!

02suburbanZ71 · September 7, 2014

Its night time out and i unlocked my 02 with the keyfob, grabbed my wallet, shut the door and locked her up. I noticed all the lights went off and the under hood light came on, all by itself. It shines bright under the truck and in the wheel well with the hood shut. I banged the light a few times and slammed the hood. Still would not go off. I hit it enough that it shut off once then when i slammed the hood it came back on. I had to unplug it so it didnt kill the battery. About 3 weeks ago i cleaned the internals of the light and the weight and never had a single problem. What should i do to try to repair it?

Doug_Scott · September 7, 2014

How do you normally turn the light on? Whatever turns it on is not working as intended. If it is a mercury type switch, then it likely just needs to be adjusted to not turn on until hood is opened. If it is a mechanical switch like at door jamb switch(or pillar switch), then it needs to be cleaned and adjusted as well.

efritz · September 7, 2014

I have had the same issue a couple times because of salt and gravel dust getting into the switch. Just take it all apart, clean and lube the slider and put it all back together.

02suburbanZ71 · September 7, 2014

How do you normally turn the light on? Whatever turns it on is not working as intended. If it is a mercury type switch, then it likely just needs to be adjusted to not turn on until hood is opened. If it is a mechanical switch like at door jamb switch(or pillar switch), then it needs to be cleaned and adjusted as well.

I guess there is a weight that moves when the hood is in the open position that engages the light to come on. To get it to work i usually have to hit it a few times but now it wont go off. Without opening hood it stays/comes on

I have had the same issue a couple times because of salt and gravel dust getting into the switch. Just take it all apart, clean and lube the slider and put it all back together.

I did about 3 weeks ago and have only driven 150 miles since and no gravel roads :-(

Doug_Scott · September 7, 2014

Have you considered getting one of those alarm switches they use for hoods and trunk lids and using that to turn the light on instead? Would be a very simple change to make.

Not having seen the actual switch it uses, I would think that going by your description that maybe the lube is working against you. If it is a sliding weight type switch, the lube could be too dense or thick and that stops the weight from moving easily with just gravity. Try a dry graphite type lubricant, or no lubricant at all.

Duelin · September 7, 2014

Is the weight flopping back and forth like it is suppose to? And are all the contacts clean and not sticking? I would say you are going to have to take it apart again and go thru everything again. And make sure nothing is sticking.