Chrysler Repair: Headlamp leveling switch: minivan export model, voltage polarity, grand voyager

Question
QUESTION: Hello,

I have taken the front headlights off of my 2000 Grand voyager to polish the fogged plastic.  I have now put them back, but it seems like the electric height adjustment doesn't work correctly.  The lights appear to raise OK, but then don't seem to go back down.  Was there some particular thing I should have done while remounting the lights?  many thanks for your advice

ANSWER: Hi Julie,
The fact that they move in one directions shows that there is an electrical connection in place. Therefore, because the reverse action involves changing the voltage polarity of the singe wire that moves the motor it would have to be either a mechanical hangup in the movement itself, within the housing that is dragging against the downward movement OR by chance the switch contact for the downward movement control in dash has a poor connection from dust/corrosion/dirt or lack of recent usage. You could buy some electronic circuit cleaner in a spray can and squirt it in the control switch if you believe that it may not have been working in the downward direction prior to your repair effort, but if it was working and now it isn't then all I can suggest is that you remove the units and check again for mechanical issues. It would seem unlikely that both sides would suffer from a mechanical issue, so I lean toward the belief that you have a dirty contact inside the switch. There are four position evidentally involved with the switch (up,down,left,right) so the down contact is evidentally not conducting as it should.
Roland

---------- FOLLOW-UP ----------

QUESTION: Thanks Roland, I will take another look. When I had the light out yesterday, I did note that the system seemed to work by a white plastic rod pushing out or retracting from a cup in the headlight housing, which in turn affects the tilt of the lamp housing inside the headlight.  When the lights didn't seem to be able to adjusted down, only up, I started to wonder if the control on the dash in the car should have been set to a particular setting, for example at one end of its range, either on zero or two...  I thought about this because it seems that if the rods were set at a different position than was set inside the car, it might affect the total mobility of the system.

This reminded me of the radiator thermostats that we have in Denmark - there is a little metal pin that moves in and out to block or release the hot water flowing through the radiator, controlled by the movement of a piece in the thermostat knob. If you take the thermostat off, it is important to put in back on in the "off" position or it won't work correctly.  it was just a thought...

Answer
Hi Julie,
If you want to check out the leveling switch function you can measure the resistance between pin 1 and pin 2 or pin 7 of the headlamp switch, with the leveling set on its three positions as follows:
On any setting, the resistance between 1 and 2 should be 3191-3400 ohms
On setting 0          1     7          3238-3456
         1          1     7          1195-1225
         2          1     7          746-765
If you get those readings then the problem is not in the switch.
Roland
PS You are welcome. Please 'rate' my answers.