I recently changed the alternator brushes in my 87 runner with Toyota brushes because the voltmeter would take a dip at the same time the charge and brake lights lit up. It's been running great for about the last month without any trouble.

Recently, driving home from work I rolled up the back window with the switch on the center console. After the window was all the way up I pushed the switch again just to be sure the window was completely up. When I did that, the voltmeter and tach needles took a dive to zero and the check engine light came on momentarily. When I arrived home, I pressed the back window switch to the up position again, while my runner was idling in my driveway and experienced the same thing. The truck kept running, but the voltmeter and tach needles dropped to zero as if someone turned the key to the off position momentarily. I tried it a couple more times with the same results. Then I turned it off. When I tried to start it up again...nothing. As though the battery was completly dead. The next morning it turned over just fine. Has this ever happened to anyone? What is going on?

Also, while driving it about the next morning, I noticed that the charge and brake lights would blink off and on dimly at first, but as I opened the throttle they would become more bright and steady.

Thanks for any help you can lend me!

 

Check all your connections, especially the grounds, with the alternator & battery. Do you experience this with any other switches (windows,etc.)?

 

I can't say I have experienced the excact same thing, but my volt meter moves quite up and down depending on the load Ihave on it while at Idle, the second I start driving the volt meter goes up. I think I need to have my alternator tested, just haven't had time.