'86 GL Hatchback: Dashlight Dimmer Switch

[TheYeti]

Hello all,

 

I have an ongoing issue with my dashlights and the dimmer switch.  The dimmer seems to work for the dash when the engine is not running.  Once started, the dash goes to full brightness and the dimmer no longer functions. 

 

While sitting at a stoplight one morning, the dash dimmed to the switch setting when I pulled down on the steering wheel.  The headlights dim while at low idle, along with everything else (this has always been the case).  Voltage drops below 12v according to the guage.  The battery is always charged, and lights are as bright as ever when RPM is around 1k or above.  There is never any "flickering" while driving.

 

There must be a bad connnection or a short somewhere.  Are there some connectors I should be checking? 

 

Any ideas to get my dimmer back are welcome.  Maybe it is just the switch itself.

 

Thanks!

 

j.

Edited February 11, 2014 by TheYeti

[ruparts]

hi,

 the switch i can't say but a good first thing you should concider the 90 amp alternator swap a lot of us are doing, use the late 80's  maxima alternator, have to change the pulley, make a connector adaptor or otherwise make the connections, and it's a direct bolt on to 90 amp .  lots of write ups about it on this board, do a search, this is a worthwhile upgrade for these cars, and not expensive , if you get a good used alt from a jy, might find someone on here selling one already to go.

 that dimming if you pull on the wheel might indicate a weak ground is some of the problem, if this is a ea81 style , there is a major ground lead up behind the fuse panel (black wire, ring eyelet, comes directly off the main wiring harness) , that sometimes is not really grounded good,  it was a source of much trouble for my 84 wagon till i  located and  fixed it.  it can cause a lot of unusual stuff with the lights and guages,, there are a lot of write ups and posts concerning it in the past, some with pics and a lot of comment.

Edited February 11, 2014 by ruparts

[TheYeti]

ruparts,

 

Thanks for the detailed response. This is for an '86 EA81 seires hatchback.  I will do a search for the posts you are describing for the ground issue.  A loose ground could easily be causing everything I describe.

[TheYeti]

I took the dash apart around the steering and gauge cluster to remove the light dimmer and switch.  Somehow the wiring for the switch managed to wedge itself between the steering and crash-bar (or whatever it is around that area).  After how ever many years of being squished in there, the insulation had worn from one of the wires.  This was causing a short.  I replaced it with another unit (thanks Sucker King) and everything works again.

Edited March 7, 2014 by TheYeti