Switched the starter, still not starting
 

Ok my supra has been out for a few months due to starting failure. I pulled the starter and put a new one in there.

prior to this the car would sometimes start and sometimes not. i could put it in gear at times and start, sometimes crank it 4 times and then it would go and if it died i would have to wait maybe 5 minutes to get her going again.

now when i go to start it just clicks. just one click like the battery is dead. checked the two wires on the starter and they are on alright. Maybe im overlooking something, if anyone has anything please let me know. Thanks

ya i have the same prob so help would be sweet

the only other thing i can think of is your battery. a battery can register good volts but it is the cranking amps that get it to start. the only way to check that is a battery tester. the only time i've ever seen one is when i worked at a dealership but i'm sure they are around. especially at a garage.

not startting
 

Here is what i would suggest, replace the positive cable that goes to the starter, disconnect the negative cable from the body and clean the stud or the firewall where it connects and use a wire wheel and clean the area and then re connect it, and if all else fails go through and check the started selinoid, clean the connection of the positive cable and the starter, and if that fails get a marine or RV deep cycle battery and that should work.


good luck with your car.


:gotnos:

This is an extremely common problem in these cars. The signal wire going to the starter gets old and starts to have resistance, not allowing full power to go to the starter trigger solenoid, therefore it can pull the solenoid so far, but not far enough to get the contacts to touch for the starter to turn. That is why you hear a single click. It is an easy fix, you just have to wire a relay into it. Wire it as such using a wire as big or bigger than the original blue trigger wire. Use these crimp on connectors, they slide strait onto the relay spades and the starter spade. With this circuit, you can use the weak blue signal to trigger full battery voltage to the starter.
RadioShack.com - Cables, Parts & Connectors: Connectors & connectivity: Crimp connectors & terminals: Crimp-On Quick Disconnects (6-Pack)
^ those come with male and female connectors, but you only need the female ones. You will need 4 female connectors so you would have yo buy two packs. Hope this helps you. If you want proof that this will work, hook a jumper wire from the battery positive terminal strait to where the blue trigger wire connects on the starter, and watch it crank everytime.

not starting
 

yes i agree that would work but why just use a temp fix when all you need to do is get a new positive cable that runs from the battery to the starter (selenoid) and then that would take care of the problem.? also you might want to have an electrical systems test done on the alternator just to be sure it is functioning the way it is supposed to be.

Because that is not the problem. There are two wires that go to the starter; the positive battery cable, which is heavy gauge, and the small, blue trigger wire, that only receives current when the key is turned to start. The problem is the trigger wire, not the big positive cable bolted to it. When you turn the key to start, current goes through this blue wire, energizes a coil of wire making magnetism, and pulls a plunger, when this plunger is fully pulled, it connects two more contacts, the positive batter cable and the bigger coil of wires that turns the starter. The problem is over time that little blue wire gains resistance internally and doesnt provide enough current to pull the plunger all the way to the point where the other contacts touch, therefore you can hear the plunger moving, but its not going enough to make the starter contacts touch. This is why people usually experience this problem more when the car is hot ( heat=more resistance). So by using this relay, you can take the small amount of current supplied by the old blue wire, and use that to switch the relay which in turn will give full battery voltage.

This is not a temp. fix at all. It is permanent. You can take out your entire wiring harness from your car, trace the blue wire back through all its connections and all the other wires its involved with, and replace them all, or you can do a simple relay mod like many many others have done.

well i am not trying to argue a point, i had the same problem with my 85 and i replaced the positive cable and it took care of the problem, so like i said i was not trying to argue a point i was just offering advice.

Copied from previous post HERE
One of the problems is the gauge of the wire, although probably ok when new, it is too thin and over the years the copper wire deteriorates, resistance increases due to age and the constant heat changes. This becomes more apparent when the engine bay heats up, the thin wire will also heat up, causing high resistance. A permanent fix is to fit a 30 or 40amp 12v relay in the engine compartment. Instructions below.

The thin wire from the ignition activates the coil in the relay which doesn’t need a lot of current. The switching part of the relay takes care of the amps required for the starter solenoid, The large wire going to the starter motor from the battery is the main power to turn over the starter motor once the solenoid is activated, this wire doesn’t need to be upgraded. Insructions;
1. Disconnect the battery
2. Fix the relay to the bulkhead or somewhere covenant.
3. Remove the thin wire going to the starter motor and connect it to terminal # 86 on the new relay
4.Connect terminal # 85 to earth (negative) using a 20 amp wireAt this stage you can check the relay is working by connecting the batteryand switching on the ignition as you would normally do to start the car. You should hear a click from the new relay but the starter will not turn over until you have competed the next steps.
5. Remember to disconnect the battery again
6. Connect a 20 amp wire to the spade terminal on the starter motor. (This is where the thin wire was once connected.) Connect the other end to # 87 on the relay.
7. Connect 20 amp wire straight to the battery and to # 30. connector on the relay. Job Done.
http://i17.photobucket.com/albums/b56/cirgriff/6.jpg

I agree with the fix as ive had the problem so bad I had to install a remote start switch and used the coinholder for mounting it. After the post by CyFi6 I went ahead and got the relay and put it in in a little over an hour and it works like a champ!!!

i had the same problem and was getting frustrated. i thought for a moment and i had a batt charger. i desulfated the batt. and then charged it up. put it in the car and she cranked right up. this was the first time in a couple months.

but like everyone is saying go from the obvious (batt) then work ur way around.

this thread did help me in a way. thanks.

i had the same problem where i replaced all the wires but still nothing......

after dissambling the starter we found out that it was the bearing that was holding it stuck.......

Starting Problem Please Help
 

Please excuse me if I don't state the Mk of my Supra or what engine model engine it has, I have only just bought it. Its a 1990 3.ltr Turbo Manual, Bought it from my father inlaw with 60K on the clock, quite tidy and I love it.

I have a starting problem where the car starts easy and runs great, but when you stop and try to re start all you get is a click from the dash and nothing, if you wait anywhere between 10 mins and 90 mins (erratic) it will start again no problem :(

Is my problem the thin blue wire and do I need to do the relay conversion ? how easy is it to do and where is the starter motor located ?

Any help would be very much appreciated as its driving me crackers. :eek3:

Sometimes the car will start as many times as you like with no problem, its erratic but sounds like the wire to the starter motor from what I have read ?

id just go to Autozone and get a new battery, and if that works then good, if not, just return it. could be its using its energy up on the initial start that it wont crank till it sort of builds up enough juice(I don\'t know a whole lot about batteries, but just get yourself a matinence-free bat, if the old one isnt matinence free then it makes things a pain in the ass when it doesnt have to be.

Battery Is OK
 

The battery is fine.

I was thinking I have the same problem as others who have had the problem with the wire to the starter motor.

Problem has been there a while, battery was replaced not long ago.

:(

http://www.toyota-supra.info/forums/...ty-system.html

possibly related to the security..

Thanks
 

Ok I have checked the battery and its fine, my father inlaw says starting problem has been a problem for some time now.

What happens is the car will start from cold no problem, always does and never fails, drive the car for a while and stop, when you go to start the car nothing, you can hear a faint clicking from the dash, but not a clicking from the solenoid, all the dash lights dim right out as you turn the key although the battery is not flat, as a rule of thumb if you wait 10 to 15 mins the car will then start no problem and you can turn off and start up again and again, somethimes it won't start for over an hour or more :( I have read the various possible causes but really would like to be sure what is actually causing this problem as I now avoid driving my Supra as its unreliable and erratic.

The car has covered 60k from new and in its time has had a head gasget and been dealer serviced on a regular basis.

Do I do the relay conversion ?

Do I check The Earth's ?

I have turned off the alarm ?

Does the Supra have a built in security system ?

Update
 

I have just checked the earth from the battery and its ok, battery terminal stays tight even when car is hot, I ran the car up to temp and turned off and re started several times with no problem, I tried to make it fail but nope it was ok, so why does it fail when it feels like it.

Battery is a good 12.5 Volts static, charge rate is good.

Someone must have had the same problem, I read the relay conversion and thought that sounded like my problem but now I have curve balls added which add the element of doubt :(

I would really love to trust my Supra and drive it but I can't sit and wait up to 90 mins each time I stop :boring: so I am :confused::frown::eek3:

You replaced the starter with a new one? If so, it has to be a power issue. The problem with checking everything is, that you are looking at what looks like a heat related issue. When the engine is hot (after you drive for some time), something happens that stops the power from getting to your starter.

Therefore (not being an expert) I would replace the blue wires as described earlier in the post, or if you want to just try something .. you can try to move wires away from the engine (trace them to the starter, and just try to ensure that none are close to the engine). Of course... I would replace the blue wires, just because its a "known issue" and thats a "known solution".

Having said all that, and here I go not being an expert - therefore giving a partial answer.... get the engine hot enough that it wont start and test the voltage at the starter post. (not sure what you should have there normally) Then when the engine is cold enough to start again, test the voltage at the starter again. See if there is a difference. That will go miles toward solving the problem. If its the same both times, it may be the starter itself. Getting a new starter, and putting it in will tell the tale. And if your careful with the new starter and it doesnt change anything, you can always return it.

The Thin Blue Wire
 

Ok I am going to do this conversion and fit a Relay and move the blue Wire, what d I need to do to access the starter motor and where is it located ?

Can I fit a Solid State Relay instead of the normal automotive type ?

Maybe best if I buy a manual for the 1990 MK III ? does anyone know where I can get one on CD ?

you?ll find it for free at cygnusx1

Relay worked!!!! (so far......)
 

I put in a relay yesterday and tightened the + on the starter and it STARTS! it sounds much stronger than before, so far so good. Thanks CYi6f and BillUK.

I have an 88 Supra all stock 5-spd and recently had it in the shop for an alternator and master cylinder. Everything was working fine accept it would randomly quit starting for no reason. (usually a sign of electrical trouble), i would turn the key and all i would hear is a click under the dashboard behind the glove box and a click from the starter. i had the starter tested and it checked out OK. I had the battery tested and it checked out ok.

i googled this forum and found this thread. i put in a 4 prong 30amp relay with 14gauge wire then tightened down the + on the starter. Original wiring was brittle and loose.(in fact i have to check all my grounds and +)

SUPRA pros- 5 spd/fast/fun
SUPRA cons- head gaskets/alarm/weight/wiring on the starter

i know this is gonna sound stupid but i have the same exact problem. only thing is how do you wire up that relay? everyone says they do it but i just want to know exacts. is a 14g wire from the positive to the relay and thats it or what? Hopefully someone can answer me. thanx

the way i did it
 

im not sure what everyone else did, As some have stated the wires get old and resistance goes up and conductivity goes down. so i used 14 gauge on all 4 wires, guess you can use any gauge wire that will handle the current. for example 14 gauge can handle 32amps. (Wire-Gauge Ampacity - Transwiki)

i guess what the 'relay solution' does is it uses the weak blue wire to flip the relay switch(instead of the starter solenoid) that in turn allows a direct draw from the battery through the relay with brand new wire. also make sure your positive on the starter is not corroded or loose. on the first page of this thread is the diagram. (5th prong not necessary unless you install a kill switch), anyway, hope this helps a little, its been 5 days in cold weather since ive put in the relay and so far no problems.

thanx guys for your reply. im going to try it out this weekand

Fixed starting problem, thanks
 

Thanks to Cyfi6 and Bill UK I was able to start my 1988 supra 7m-gte, I replaced the strarter which I tested and it was burned out, had problem with top bolt but was able to reach it with a 2 foot extension and universal socket with a 14mm attached and I reached it from the front of the car with my hand under the exhaust manifold and I used the weight of the starter to hold the bolt from moving while I unscrewed the nut. Then I jump started it and it started, but when I cut it off it wouldn't start again, so I came to this forum I purchased the 30 amp relay plus 18 gauge wire and wired it first based off the wiring diagram that Cy Fi6 posted and it didn't start so I wired it based off of Bill UK wiring diagram and it started right up and has continued to start everytime. I'm in chicago so it was very cold when I changed the starter out and put the relay in.

I could not have done it if this forum did not exist so thanks to this forum admin (cre) and a special thanks to Bill UK and CY fi6

I'm having similar issues. I think i'll try it. i'll repost after see if it helped

Where?
 

had same problem...anyone has a diagram where the starter relay located? thanks.

The stock diagram? Here: http://www.cygnusx1.net/Supra/Librar...x?S=Main&P=038

Hey Cre, I try to buy today at NAPA auto parts the starter relay and they said its not listed...where can I buy this? and I cant find where is it located inside my car so I cant take it out and show it to NAPA. please help thanks.

Where
 

Where can I find this in my car Toyota Supra 1988 7mgte? and where can I buy it? NAPA said its not listed on them. Please help thanks.

That is not a Toyota part. It's a standard Bosch 30/87 SPST automotive relay. This is a hack to work around an age related issue which many experience with this car. This is a circuit you ADD to your vehicle. You can find these relays in the lighting section of most auto parts stores for $1 to $5 (depending on the shop and the area).

Thanks man...just got confuse of this starting headache when my engine gets hot, wont start...i will try this. Thanks bro.

Check for diagnostic codes first. Heat may cause a failing starter or wiring from cranking but there are other possibilities as well. If it's a failing starter or other component this rewire will be a pointless headache.

Thanks CRE, my starter is new and alternator, battery is good. But just now I have a new problem...when i turn on my headlights, it wont come on but instead I hear a continuous clicking sound on one of the relay in driver side and the big relay on engine compartment and my dash board light on and off, it happen before and i thought its only a loosen relay coz when i push it, it works but now it wont work that way anymore, any idea what is this? i appreciate all your help man.

Starter shorted?
 

I jacked my MKIII up and attached a wire to the blue and black wire tabbed location brown clip on the starter and ran it to the positive terminal of my battery and it acts like it is shorting out when I touch positive wire to the battery terminal. I was following instructions I read on the site as to how to test the activation wire to the starter. The car sat for a couple of years but the starter worked fine when I parked it does anyone have an answer for this? Does this mean the starter has somehow gone bad just from sitting?

The wire sparks when I touch it to the positive terminal seems to burn slightly but not like a full short. The Starter does nothing. I have full battery and the car only clicks when I try to start it. Could a short have developed within the starter just from sitting?
Please respond. Thanks

Starter / Alarm System / OEM relay ??
 

I hope some smart people are still around here on the forum...
I'm the original owner of MkIII 86.5 NA

I've been having starting issues and am aware of the common problem with the blue trigger wire not supplying adequate juice to fully pull in the solenoid, and the relay-fix. I have NOT yet installed that upgrade but likely will do so very soon...
except today ... it's cold raining and my Supra won't start.

I have good battery (6 mo old, fully charged).
I recently replaced starter motor which may not have been 100% necessary,
but before I turned in the core I took it apart and if it wasn't causing some issues ...
it was going to be doing so soon brushes and contacts in poor shape.


if there is any talent on deck - I have two Questions please:


1) Has anyone ever found the OEM starter relay on the passenger side kick panel to be a problem?

Item "C" in this pic:
http://www.cygnusx1.net/Supra/Librar...aspx?S=BE&P=14

Starter relay center right in this diagram:
http://www.cygnusx1.net/Supra/Librar...x?S=Main&P=038



2) I have had issues in the past with the alarm system ... so would like to eliminate that as a potential issue.
One proposed way to disable the alarm system permanently is to unplug the alarm switch at the hood latch
since it is easy to get to ... I think it was @cre that suggested this?


It appears to be the 2-pin black connector at rear of hood latch assby?
Do I just unplug it or do I jumper across the harness side of the connector? That part was not clear....


Thanks!
Jim