brake and charge light on in instrument panel

[doktasoohs]

Hey all I have the dreaded brake and charge light on in my 1984 pheonix, I did some googling and found out the earlier toyotas have a diode in the alternator or something like that that goes bad. I bought my replacement alternater from autozone and same problem and battery goes dead (not charging) can anyone point me in the right direction i want to tackle this problem saterday. do i need an oem part or is thee a way to fix what i have or???

[Shoprat]

Hey all I have the dreaded brake and charge light on in my 1984 pheonix, I did some googling and found out the earlier toyotas have a diode in the alternator or something like that that goes bad. I bought my replacement alternater from autozone and same problem and battery goes dead (not charging) can anyone point me in the right direction i want to tackle this problem saterday. do i need an oem part or is thee a way to fix what i have or???

I had the same problem and it was tha three wire battery isolater. I replaced mine with an old fashioned mechanical relay, and the problem went away.

Hope this helps.

John

[bufbooth]

My brake and charge light comes on if my coach battery is disconnected.

Be sure that you coach battery is connected.

Dennis...

[Maineah]

If you have a solid state isolator there are a few things that you will need to check. If it has a relay type it should have no effect on the charging of the truck battery. The solid state isolator should have 4 terminals 1,2,A and "E" the "E" terminal must have power when the key is on if it does not it will not charge. The 1 and 2 terminal should have power all the time key on or off. The "A" terminal will have no power with the key off and should have power with the key on if there is power at the "E" terminal and not at the "A" terminal with the key on the isolator is toes up. If all of that is good the next trick is to jumper the terminal (1 or 2 what ever one goes to the truck battery could be either you'll have to check)to the "A" terminal if it charges then the isolator is toes up. Shorts and batteries hookup backwards even for an instant will kill a solid state isolator in a heart beat.

[doktasoohs]

when i bought this thing it had no isolator, the guy had pulled it out. I reconnected the wire that they cut to put the isolater in at the factory so my wiring is stock 1984 toyota p/u style. the wire going to the coasch battery ius disconnected as i use solar for everything coach related for power.

[Maineah]

when i bought this thing it had no isolator, the guy had pulled it out. I reconnected the wire that they cut to put the isolater in at the factory so my wiring is stock 1984 toyota p/u style. the wire going to the coasch battery ius disconnected as i use solar for everything coach related for power.

I'll have to find my wiring diagram files for a color (I think it is white with a black stripe) but you will need to have a look at the "ig" terminal at the alternator they may have cut the wiring to fit it to the "e" terminal on the isolator. There is a terminal on the alternator that is powered on with the key it wakes up the alt and shuts it down with the key off so you might check to see if you have power there it won't charge with out it.

[joetiff]

I'll have to find my wiring diagram files for a color (I think it is white with a black stripe) but you will need to have a look at the "ig" terminal at the alternator they may have cut the wiring to fit it to the "e" terminal on the isolator. There is a terminal on the alternator that is powered on with the key it wakes up the alt and shuts it down with the key off so you might check to see if you have power there it won't charge with out it.

Can anyone tell me where the SINGLE back wire goes to from the alternator on a 1982 1983 or 1984 I am told are all the same. 22 r

thank ya

Pics would be very helpful

[Maineah]

Can anyone tell me where the SINGLE back wire goes to from the alternator on a 1982 1983 or 1984 I am told are all the same. 22 r

thank ya

Pics would be very helpful

From what I see it goes the the "E" terminal on the regulator. Now question is does it have an "E" terminal "E" in overseas wiring is earth or better know over here as ground. It may just ground to the regulator with a screw.

[joetiff]

From what I see it goes the the "E" terminal on the regulator. Now question is does it have an "E" terminal "E" in overseas wiring is earth or better know over here as ground. It may just ground to the regulator with a screw.

We must be talking about 2 two different black wires that come off the alternator, 1 goes to the external voltage regulator and the other black wire is a single wire that mounts directly above the main alternator harness, this wire is hot when the truck is running so it cant be a E or a ground wire. Is it possible that some one has changed the wire to black, from who knows what color. ANY more suggestions appreciated, help I leave for Oregon in 3 days, for some salmon fishing and visiting family

[Maineah]

We must be talking about 2 two different black wires that come off the alternator, 1 goes to the external voltage regulator and the other black wire is a single wire that mounts directly above the main alternator harness, this wire is hot when the truck is running so it cant be a E or a ground wire. Is it possible that some one has changed the wire to black, from who knows what color. ANY more suggestions appreciated, help I leave for Oregon in 3 days, for some salmon fishing and visiting family

OK here is what I show for an external regulator. L= yellow E= black F= green S= white and ign= red alternator end L= yellow F= green B= white and E= black (ign is not used at the alternator) there are exceptions (4X4 and cold weather package) but the only black wire is still "E" hope that helps you. The B terminal will be hot all the time it goes to the battery (#8 wire) the L terminal is what does the light probably will do nothing until the alternator is charging, the F will have some voltage with the key on, the e terminal is ground.

[joetiff]

OK here is what I show for an external regulator. L= yellow E= black F= green S= white and ign= red alternator end L= yellow F= green B= white and E= black (ign is not used at the alternator) there are exceptions (4X4 and cold weather package) but the only black wire is still "E" hope that helps you. The B terminal will be hot all the time it goes to the battery (#8 wire) the L terminal is what does the light probably will do nothing until the alternator is charging, the F will have some voltage with the key on, the e terminal is ground.

The B terminal will be hot at all times you stated # 8 wire, would this be the single wire that goes to a lug on the alternator ? the lug is directly above the other lug that the group of yellow=black-green-white-red wires plug into the alternator.

I have tried to upload some pics, but it is not working for some unknown reason, I think I may have to create a account somewhere on the www, to upload some pics if need be.

thanxs for you patience and understanding.

[Maineah]

The B terminal will be hot at all times you stated # 8 wire, would this be the single wire that goes to a lug on the alternator ? the lug is directly above the other lug that the group of yellow=black-green-white-red wires plug into the alternator.

I have tried to upload some pics, but it is not working for some unknown reason, I think I may have to create a account somewhere on the www, to upload some pics if need be.

thanxs for you patience and understanding.

Yes that is the output from the alternator the rest are what regulates the output and sends a signal to the charge relay.

[joetiff]

THANK-YOU

So this wire goes directly to the battery + " Positive "

Thank-You

Now I have another wire that is in question---it is a white wire with blue dashes- that has also been cut. Iam begining to feel these wires must of went to a battery isolator our something.

[Maineah]

THANK-YOU

So this wire goes directly to the battery + " Positive "

Thank-You

Now I have another wire that is in question---it is a white wire with blue dashes- that has also been cut. Iam begining to feel these wires must of went to a battery isolator our something.

Isn't it grand working on 20+ year old stuff. There are a lot of people out there that twist two wires together and if it does not kill them then they figure they know all there is to know about wiring, sounds like they have had a hand in your wiring. If your alternator wiring is still intact not cut patched and taped they probably did not have a solid state isolator hooked up. As near as I can tell your white/blue wire should have nothing to do with your charging system. Test it for power try it with the key on too if you don't get any thing it may have had some thing to do with the emission systems that used to be the way to fix running problems if we don't understand it cut it off don't need it any way!

[joetiff]

Isn't it grand working on 20+ year old stuff. There are a lot of people out there that twist two wires together and if it does not kill them then they figure they know all there is to know about wiring, sounds like they have had a hand in your wiring. If your alternator wiring is still intact not cut patched and taped they probably did not have a solid state isolator hooked up. As near as I can tell your white/blue wire should have nothing to do with your charging system. Test it for power try it with the key on too if you don't get any thing it may have had some thing to do with the emission systems that used to be the way to fix running problems if we don't understand it cut it off don't need it any way!

Oh yes GRAND it is !

And it appears they had a hand in this wiring.

the white and blue wiring has 12.6 volt when the ignition is on or truck is running.

the battery is showing 12.77 v at idle, when I turn the lights on radio, wipers etc, it draws the voltage down on the battery to a mere 11.50 v.

I am seeing signs of a cut and patch job where a battery isolator or something was attached to the inner fender well, but is no longer there. Can you or anyone help me with finding a new relay type isolator and help me wire this ol girl back to the way she was before someone put there hands in it. Or just get it back to orginal, don't really need the house battery.

I have started to read about this to help me understand how it all works, but personal knowledge is most often understood better at least by me : }

[joetiff]

Oh yes GRAND it is !

And it appears they had a hand in this wiring.

the white and blue wiring has 12.6 volt when the ignition is on or truck is running.

the battery is showing 12.77 v at idle, when I turn the lights on radio, wipers etc, it draws the voltage down on the battery to a mere 11.50 v.

I am seeing signs of a cut and patch job where a battery isolator or something was attached to the inner fender well, but is no longer there. Can you or anyone help me with finding a new relay type isolator and help me wire this ol girl back to the way she was before someone put there hands in it. Or just get it back to orginal, don't really need the house battery.

I have started to read about this to help me understand how it all works, but personal knowledge is most often understood better at least by me : }

Going to push my trip to Oregon off until I can get this thing back to normal with or without a house battery.

[doktasoohs]

This thing is a pain, ok i took it to the shop, they said i did not have power at the pass side (under the hood) fuse and they fixed that, they then told me the alt (brand new one) wasnt working. took it back to autozone and they refunded my money after it tested 3 times in a row bad. bought another one at napa and yay it works but not so fast, it was reading 16.5 volts at the battery when idling. that will cook my battery so i went back to the garage that worked on it and we both agreed it must be a bad voltage regulater (bolted under the hood on the drivers side fender)so i ordered one from napa, they asked do i want the 40 dollar one or the 80 dollar one? i went for the 80 i mean 100 dollar after tax one. after two weeks it finally arrived and i installed it and guess what? the frigging voltage is now 17.0 volts at the battery at idle. what am i doing wrong? driving me nuts, of course this is after spending thousands on the rest of the motorhome installing solar, entertainment, complete renovation on the inside of the coach etc. am at a loss for words but i will percevere, this is my dream motorhome and by golly i will ressurect it to a stand alone off grid high mpg (18+) cruiser. any thoughts? would love to hear any ideas on this.

[Shoprat]

Just for giggles, check the ground cable on the battery. Some times people get so involved with the supply side of things, they forget that it has to return also. Maybe a bad connection at the negative battery cable connection to the engine or battery. Watch for green gunge in either cable near the battery. Hope this helps.

John

[doktasoohs]

Just for giggles, check the ground cable on the battery. Some times people get so involved with the supply side of things, they forget that it has to return also. Maybe a bad connection at the negative battery cable connection to the engine or battery. Watch for green gunge in either cable near the battery. Hope this helps.

John

did that allready, good clean ground and ground wires.

[Maineah]

The alternator is fine it's doing what it is told the "F" or green wire voltage is what controls the charge rate, full battery voltage at the green wire will cause it to charge full tilt be careful an unregulated alternator is capable of pretty high voltage enough to damage things. There is quite a dance inside of the regulator to control the field voltage it's not for nothing they went to solid state regulators. Make sure your "B" terminal (white wire) at the regulator has power all the time and that it is at battery voltage.

[joetiff]

The alternator is fine it's doing what it is told the "F" or green wire voltage is what controls the charge rate, full battery voltage at the green wire will cause it to charge full tilt be careful an unregulated alternator is capable of pretty high voltage enough to damage things. There is quite a dance inside of the regulator to control the field voltage it's not for nothing they went to solid state regulators. Make sure your "B" terminal (white wire) at the regulator has power all the time and that it is at battery voltage.

I do not understand yet how the white wire at the B terminal on the voltage regulator can go directly to the B lug on the alternator and then to the positive battery terminal. If somebody would like to show me a picture or draw me a picture this would be great. Is all that is happening here is a basic 1983 truck wiring as I have no coach battery or isolator. I bought a chilton and haynes manual but they is not helping me. PLEASE explain. Thank You

[Maineah]

I do not understand yet how the white wire at the B terminal on the voltage regulator can go directly to the B lug on the alternator and then to the positive battery terminal. If somebody would like to show me a picture or draw me a picture this would be great. Is all that is happening here is a basic 1983 truck wiring as I have no coach battery or isolator. I bought a chilton and haynes manual but they is not helping me. PLEASE explain. Thank You

The white wire from both the alternator and the regulator have power from the battery they do not turn off with the key. When I say they go to the battery they may do so via the fuse panel buss in the case of the alternator it goes directly to the battery through what is known as a fuse link. From the factory there was a a bolt on the positive battery terminal that may have had two or 3 wires under it. Yours is a Tirrill type regulator it is not a IC type it is a 40/55 amp alternator. There were options but yours is not one of them so if you are looking at your book disregard the IC type alternator/regulator.

[joetiff]

The white wire from both the alternator and the regulator have power from the battery they do not turn off with the key. When I say they go to the battery they may do so via the fuse panel buss in the case of the alternator it goes directly to the battery through what is known as a fuse link. From the factory there was a a bolt on the positive battery terminal that may have had two or 3 wires under it. Yours is a Tirrill type regulator it is not a IC type it is a 40/55 amp alternator. There were options but yours is not one of them so if you are looking at your book disregard the IC type alternator/regulator.

Well I must have a few missing brain cells, and it is going to take a picture or a drawing, to understand this white wire. Is this what you are saying is the white wire that goes out of the voltage regulator terminal B goes to the top of the alternator lug B with a inline fuse, then a connection " wire " also comes off that same lug B on the alternator and goes directly to the POSITIVE battery post with a inline fuse, is this correct? Hows about a picture it could surely only help, some times pictures will help it click with people like myself that just dont understand. What size guage is this white wire that we are talking about at the Volt reg and at the alternator to the battery ?

PLEASE send a picture or a drawing.

Thank-You

[joetiff]

Well I must have a few missing brain cells, and it is going to take a picture or a drawing, to understand this white wire. Is this what you are saying is the white wire that goes out of the voltage regulator terminal B goes to the top of the alternator lug B with a inline fuse, then a connection " wire " also comes off that same lug B on the alternator and goes directly to the POSITIVE battery post with a inline fuse, is this correct? Hows about a picture it could surely only help, some times pictures will help it click with people like myself that just dont understand. What size guage is this white wire that we are talking about at the Volt reg and at the alternator to the battery ? Wow this just dont make sense to me !

PLEASE send a picture or a drawing.

Thank-You

Mainah-can ya draw me a pic while you recouping from foot surgery ?

Anyone please help.

[Maineah]

Both wires are hot all the time how they arrive at this I can’t tell you because I have never cut open a wiring harness to find out. What I can tell you is the (“B”) (white wire) from the alternator goes directly to the battery through a fuse link it does not go any where else. If both wires are receiving battery voltage it is the same as having them joined together. There is a connection in you fuse panel that goes to the battery post along with the alternator wire it feeds the regulator wire through a fuse and some other things in the MH that have power all the time like your dome light. Look at it this way if you have a “T” in your water pipe both receive water from the same source. The white regulator wire and the white alternator wire both go back to the battery but by a different path if you look carefully you will see that they are different sizes.

[joetiff]

Both wires are hot all the time how they arrive at this I can’t tell you because I have never cut open a wiring harness to find out. What I can tell you is the (“B”) (white wire) from the alternator goes directly to the battery through a fuse link it does not go any where else. If both wires are receiving battery voltage it is the same as having them joined together. There is a connection in you fuse panel that goes to the battery post along with the alternator wire it feeds the regulator wire through a fuse and some other things in the MH that have power all the time like your dome light. Look at it this way if you have a “T” in your water pipe both receive water from the same source. The white regulator wire and the white alternator wire both go back to the battery but by a different path if you look carefully you will see that they are different sizes.

Thank-You

Got it all wired back the way it was from the factory and we are now charging

You have been awesome explaining everthing to me and the way it is supposed to work. Thanxs much o

[doktasoohs]

well so far it is not fixed but progress has been made, i had bought a new alternater, it was bad so i had to buy another one, it was good but turns out it is for a 22re not a 22r, got it replaced again and now the regulator (second one bought so far) is the wrong one, have to take her back tomorrow on monday to put the 3rd regulater in and that is supposed to fix it. dash lights are off now as well, will keep you all updated.

[Maineah]

well so far it is not fixed but progress has been made, i had bought a new alternater, it was bad so i had to buy another one, it was good but turns out it is for a 22re not a 22r, got it replaced again and now the regulator (second one bought so far) is the wrong one, have to take her back tomorrow on monday to put the 3rd regulater in and that is supposed to fix it. dash lights are off now as well, will keep you all updated.

Is this an internal IC regulator? Or a regulator bolted to the fender.

[doktasoohs]

Is this an internal IC regulator? Or a regulator bolted to the fender.

bolted to the drivers inside under hood fender

[Maineah]

Ok I think there were two types Tirrill and Nipon Denso. There is a way to use the newer alternators if all else fails they were an option on early Toyota's. The IC or internal regulated alternators had a higher output.