Chrysler Repair: 1989 Chrysler sundance hi/lo beam problem, electronic circuit board, tilt column

Question
thank you for taking the time to try to answer my question.my lo beams are not working and stopped all at once but the hi beams work fine

Answer
Hi David,
It looks to me like the problem is in the headlamp dimmer switch as both the low and high beams are powered from the headlamp switch and the choice between low and high occurs at the dimmer with no other fuses/switches involved that could stop the action to the lows. The power comes into the dimmer on the light green wire from the headlamp switch. Then the dimmer switch either gives power to lows (violet trace wire) or the highs (red/orange trace). So you might try cleaning up the internal contacts of the switch with electronic circuit board cleaner from a spray can and if that doesn't work replace the switch. The dimmer switch is located on the column you will find the switch down the column on the other side from the ignition switch at the igntion switch level on the column. (I believe that if you have a non-tilt steering column that the switch is immediately accessible; if you have the tilt column then I need to copy and mail you pages that show how to take apart the column to get to the dimmer switch; either way let me know if you don't see how to get to the switch and tell me which column type you have*). If you pull its plug you should find continuity between B and L when on low, and between B and H when on high. There is an adjustment procedure to take up slack in the rod connection from the dimmer actuator arm to the switch. So you might try moving the switch to take up slack in the rod if that might be the cause of the lack of connection between B and L when you have it in the low position. The diagram shows an adjustment pin (u-shaped) but it is not clear if that is permanently in place or just comes with a replacement unit and for initial installation/adjustment. But in any case the problem is centered at the switch proper either the internal switch contacts or an adustment of the rod.
Roland
*It costs me 10 cents a side plus postage to get copies to you. Let me know a postal mailing address and I will let you know the costs, and you can send me back postage stamps to cover my costs after you receive the pages.