On one of my JY runs with Bill, I got a semi decent headlight switch for my 94. It had some crap that needed to be cleaned up before installation took place, so lastnight I decided to not only clean it, but tear it apart. What I found was interesting. Based upon my inspection this seems to be another failure related to plastic parts. Yes plastic.

Sorry for the low light pics but my camera sux and its on the list of things to upgrade.





Here is the switch together


There is a spring release on the switch that allows it to come apart as such


Next, there are two tabs on either side that need to be pryed up in order to remove the cover


Once the cover is off, the mechanism is quite simple and easy to figure out.


This is the plastic peice that holds the metal part that glides over the potentiometer. The metal ring, as I call it, goes onto the plastic only one way and the shaft for the switch runs through the entire assembly


After removing the plastic part, I noticed a black ring around it which indicates burnt plastic. Here is where I believe the failure takes place


The metal ring slides over that plastic part and then is held in by the metal bracket on the switch. When the plastic is new, there is very little movement for the metal ring to move.

Over time when the plastic heats up and burns, it reduces the plastics ability to hold the metal ring against the potentiometer firmly, which results in sporadic dashboard dimming control and the failure of the headlight switch.

This is just a theory upon my inspection of the switch and its componants. The onlly testing that I have done was to measure the amount of play of the metal ring while the switch was assembled. There was some noticable play but I still believe it to be in better shape than my switch that is currently installed.

Let'* note..this is on a 1994 switch. 1992, 1993 and 1995 are all different switches.

Thanks for clearing that up Bill. I thought it was one switch for the 92-95 and another for the newer models.

I was searching through the forum for a post like this one! I have a 93 SSEi that I am about to replace the headlight switch in with one I got from a 1995 SSEi. Are you saying that the two switches ARE different?? It would be good to know what the differences are before I start tearing the dash aprt in the '93. Any info you could post about the differences would be helpful, thanks

Paul

Yup, you should have seen mine when Bill and i did my dash

Remember that Bill? It was just falling apart

Ok.. you see above a 94 switch. The 93 will be similar...but completely different including connector.

Here'* a link with the 95/96-99 switches (Search is our friend)
http://www.bonnevilleclub.com/forum/...adlight+switch