Just this past weekend I changed out the turn signal/headlight/wiper arm combo unit with another I pulled from a junkyard. It was an exact match. 1991 Toyota 4X4 Ext. Cab. All numbers matched up.
My old one was missing the plastic end-cap on the wiper arm so, I could never use the wiper fluid.
All went well until I was driving to work Monday morning and my dashlights all went black and my headlights went out for a second. I just wiggled the turn signal arm and it al came back on. It did this a few times.
Yesterday afternoon I tore it all apart again and tried to search for the problem, checked the wires and even tried the old one once again. Everything seemed fine and I had no luck finding the source of the problem.
This morning it did it again. As I was driving, the dash lights all went black again. Headlights stayed on though.

Anyone got an idea??

 

Got a short in the harness???

 

It might be a dirty contact in the switch.you might try spraying it with electrical type cleaner.I have also used wd-40 to clean connections when the other stuff wasn't handy.

 

Could possibly be a short somewhere. The truck I pulled it from had been sitting in the junkyard for several years, according to the employee there.
Totally didn't even consider spraying it with electrical parts cleaner....and I have a can of it in my garage. That will be my next move.
Hopefuly it's just a little weathered and corroted and the cleaner will resolve it. Otherwise, looks like I'll be putting the old one back on and going w/out the windshield wiperfluid.

 

A buddy of mine used a squirt bottle for about 2 years...Just had to slow down to get the passenger side.

 

lmao...
a squirt bottle?
i bet he had no problem aiming at other cars

 

The fault is probibly in the combo switch.

You can remove and install the wiper part into your old combo switch, or vice versa for the light switch.

You have to remove each wire from the harness clip and replace it with the new one, but working one at a time its easy stuff.

I did this to swap in INT wipers in my girls 4runner..

 

I was wondering if you could do that. I plan on tearing it apart again this weekend and spraying it down first. See how that works. If it's no better, then I'll try your advice and keep my fingers crossed.