Yes, Buddy, my 83 alternator died a few times and as soon as that happens the E-brake light comes on all the time. This is normal. Below 12 is not good.. rev up the engine a little and it should go up to at the very least 13 to 14 volts. Your year/model has a 65 amp. You may want to convert to 80 amp while your at it..There are a few threads on this mod. You have an 1985 so its an easy upgrade to 80 (or 100 amp if you got a big stereo system)

http://www.celicasupra.com/vbforums/showthread.php?t=3161&highlight=alternator

 

Thanks for the info and reassurance.

 

uhhh, its not necessarily the alternator, dont jump to conclusions. check the battery first, if it checks out fine, THEN its the alt. remember, a bad battery that makes the alternator overwork itself will also show the batt+brake light illuminated. matter of fact a toyota truck came into my job the other day. both lights on, thot it was an alt, turned out just a bad battery.

 

a bad battery that makes the alternator overwork itself will also show the batt+brake light illuminated.

If it is indeed a bad battery (like one of cells is toast), then USUALLY the voltmeter will be showing a overcharge condition (voltmeter will around 15V or more).

When a couple battery cells in my 4 month old battery decided to "dissolve" in my 80 MKI Brownpra, my voltmeter was over 15V. Replaced the battery (still under warranty), and all was good.

BuddyJ. The dashboard voltmeter will indicate slightly below 12V at idle, but the BEST way to test this, is at idle & connect your digital multimeter to the positive connection. This will be proof positive, rather than relying on what the dash is saying. If it's showing 11V or below, that's not good.

 

If your car was at 13-14 volts Id have to say your voltage regulator has blown. Your battery has probably weakened now due to all the stress even though 12 volts is usually normal for our cars. Id check the battery if its leaking or bloated and get it tested.

 

If your car was at 13-14 volts Id have to say your voltage regulator has blown

In which case he will still need to replace the alternator... On the 85/86's, the voltage regulator is a internal one inside the alternator & not seperate like on the early MKII's & all the MKI's.

 

dude just take out the battery and get it tested. stop wondering thinking blah blah. simple as that. if battery tests out fine, you have ur culprit. if it tests bad and u put in a new one and u still have the same problem. then u know wat it is as well. a bad battery is a bad battery. if its bad, no matter what the situation was that killed it. its bad, nothing its gunna bring it back.

 

I can tell you for sure on my 83 it will not give a charge light for a bad or dead battery. I know, I have owned the car since new and have had many many dead and defective batteries and killed many an alternator. Mostly when it was a 55 amp. (oil leaking on alternator and big stereo systems and trying to charge up dead batteries) Since the time I did the 80 amp upgrade... no more problems.
But I agree.. do the easy thing first. Have the battery AND the alternator tested.

 

In which case he will still need to replace the alternator... On the 85/86's, the voltage regulator is a internal one inside the alternator & not seperate like on the early MKII's & all the MKI's.

Yeah but it sounds like hes going to have to replace the battery as well if it was taking that kind of abuse. Cant you still replace the internal voltage regulator? I remember on one of the alternator upgrade threads someone was showing how to do it or something.

 

In which case he will still need to replace the alternator... On the 85/86's, the voltage regulator is a internal one inside the alternator & not seperate like on the early MKII's & all the MKI's.

Chris,
Actually all stock MKII alternators (82-86) have internal voltage regulators. The 82 & 83 are just a different style and more of a PITB to replace since the regulator leads are soldered to the rectifier rather than secured in place with phillips head screws (84-86).


Pages 5-16 & 5-17 in the Haynes manual show some good pics. of the different style alts...... but the years are all screwed up. Figure 16.2a on page 5-16 shows a pic. of the MKI alt. with external regulator. Figure 16.2b shows a pic. of the 84-86 style alt. with internal regulator. Figure 17.2 on page 5-17 shows a pic. of the earlier style MKII alt. (82 & 83) with internal regulator.

 

I can tell you for sure on my 83 it will not give a charge light for a bad or dead battery. I know, I have owned the car since new and have had many many dead and defective batteries and killed many an alternator. Mostly when it was a 55 amp. (oil leaking on alternator and big stereo systems and trying to charge up dead batteries) Since the time I did the 80 amp upgrade... no more problems.
But I agree.. do the easy thing first. Have the battery AND the alternator tested.

The charge and brake lights in the dash cluster will generally both stay On if the voltage regulator in the alternator craps out in such a way that battery voltage is no longer present on the "L" terminal of the voltage regulator. Both lights should only stay On with the engine running if the voltage regulator is damaged for whatever reason and not providing output on the "L" terminal.

 

wow, i can't beleive someone actually searched first for the answer then asked...great job man, lol good luck with the electrical issue. Most likely the alternator...have fun keeping your supra in tip top shape.

 

It was the alternator. I replaced it Sat. morning without any problems. The hardest part about replacing the alternator is getting the alternator out of the engine bay. It's darn near impossible to remove by pulling it up through the bay. You hit the water pump or the 02 Sensor. It took me a minute to realize I should just unscrew the corner of the debris shield, allowing the plastic to flex enough to pull the alternator out from the bottom.

With it all re-installed, everythign went immediately back to normal. Voltage reads just over 12v and the brake light turns off like its supposed to. I'll check the battery, just to be cautious, but everything is running like normal now. Thanks for the help guys.

 

Thanks BuddyJ for getting back to us and letting us know how you made out. Glad you got it fixed

 

Thanks BuddyJ for getting back to us and letting us know how you made out. Glad you got it fixed

ditto

 

No, the hardest part to changing my alternator was...when I went to install it, the previous jackass had backed the tensioning nut off about 1.5 inches! So I had to turn it back 1/8 of a turn each time with an ignition wrench between 2 blades of the fan. I will know better next time!

 

Yeah, I did that too... Thank God for short 10mm open ended wrenches. That part was tedious.

 

the batt/brake light indicates under and over voltage. under voltage(different from no output) could be a few different things, over is almost always the regulator. to have mine rebuilt(before i got hired) at a local mom and pop shop was 70 CAD
25 labour plus the brushes and regulator

 

the batt/brake light indicates under and over voltage. under voltage(different from no output) could be a few different things, over is almost always the regulator. to have mine rebuilt(before i got hired) at a local mom and pop shop was 70 CAD
25 labour plus the brushes and regulator

:dead hors lol this is the problem with not reading an entire post....lol

 

eh?