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ignition switch relay (replacement?)


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Does anybody know which relay in the fuse box inside a Loyale controls the ignition? When my Loyale won't start (intermittent occurence.) there's a click from the fuse box and a click from the starter under the hood.

All wires and grounds under the hood check out. Ignition switch itself is good. I want to replace that relay and see if that might help.

Maybe I can swap the one from my GL to the Loyale to see if that makes any difference?

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  • 3 weeks later...

Well, sitting in the Loyale right now, where I've been for about half an hour. Won't start. Turn the key to on and the fuel pump primes. Turn it to start and the starter clicks, as does a relay either in or behind the fuse box, and the check engine light pulses a bit. Release, repeat, click. Click. Click.

 

Usually after trying a couple times it will eventually turn over and start. Not so far this time.

 

I do know for a fact that if somebody pulls over and gives me a jump, it will start.

 

What's up with this and why is it so intermittent?

 

Just started. After another round of about 7 cycles of the key.

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To add:

 

Got the car to a parking spot, shut it off, waited a moment and started it back up.

Started up no problem.

 

Did this four or five times. No problem.

 

Then I shut it off and turned on the wipers, headlights, high beams, HVAC fan at full speed, and rear defroster, and the dome light, and tried to start it. No start (click).

 

Held the key on and one by one turned the electrical components is, it eventually started.

 

Shut it off and tried to start with no electrical load. It started again.

 

Shut it off and tried with the rear defroster on. Wouldn't start.

 

Held key to start and turned off the rear defroster and it started when I shut it off.

 

Shut it off and tried to start it with no electrical load again. No start. Click. Click.

 

That's when I started typing this post, about five or six minutes ago.

 

It's been sitting with the key off. Going to try it now;

 

On the thirteenth cycle of the key, it started. The other 12 were click, click, click....

 

Shutting off and restarting (no load);

 

Started right up, first try.

 

Repeating;

 

Felt like a momentary delay but started first try.

 

Again;

 

Instant start.

 

One more time with no load;

 

Instant start.

 

Starting with rear defroster on;

 

Started right up.

 

Starting with rear defroster and HVAC fan on high;

 

5 tries, no start (click!)

 

Held key and shut both off;

 

No start.

 

Cycled key;

Started instantly.

 

Tried just now to start with just the HVAC fan on high and got no start. I'm done.

 

Any ideas? This doesn't happen too often but when it does it's embarrassing for my girlfriend, and it's annoying as all Hell. :-\

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The ignition relay controls the on position of the key, but not the starter. The click you hear is the fuel pump relay as it primes while on, and engages while cranking. The problem is likely the starter plunger contacts itself, or the ign switch behind the key cylinder.

 

try these:

 

start in neutral, if it goes, suspect park switch.

 

Jump the sarter from the small tab on the starter to the battery, if she goes, suspect the key switch. If no go, suspect the starter itself.

 

But since you asked, the fuel pump and ign relays are located on a bracket above the steering column above the ECU. Good luck

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Thank you fox. Starting in neutral has been tried, doesn't work.

 

Will try to get the car into a non start situation again (seems like with lots of accessory electrical load this is attainable) and try jumping the starter itself.

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This sounds a LOT like what happened to me in my brat recently. My first post in the thread i linked is misleading. It was acting like it didn't have enough juice to start, but I was misdiagnosing the problem. It was basically just like what you're describing. The fix detailed in the thread worked perfectly.

 

http://www.ultimatesubaru.org/forum/topic/147906-84-brat-intermittently-grounding-out/?do=findComment&comment=1244109

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My Loyale did the same thing. 

 

I replaced the starter contacts and that solved my problem, cheap and easy.  Make sure you have a good battery too, with enough cranking amps. 

 

Old batteries, or cheap batteries, just don't put out the necessary amps as they age.  This is why a jump start works, it supplements the weak battery and overcomes the poor contacts with lots of amps.

Edited by Dee2
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My Loyale did the same thing. 

 

I replaced the starter contacts and that solved my problem, cheap and easy.  Make sure you have a good battery too, with enough cranking amps. 

 

Old batteries, or cheap batteries, just don't put out the necessary amps as they age.  This is why a jump start works, it supplements the weak battery and overcomes the poor contacts with lots of amps.

 

Same thing with installing the relay. Instead of all of the power necessary to start the car having to flow through the entire ignition circuit, just enough to trigger the relay has to. Once the relay is triggered the starter gets power straight from the battery. It skips all of the old contacts and ancient wiring.

 

The relay was like $5 and I had a few feet of wire laying around.

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  • 1 month later...

Old batteries, or cheap batteries, just don't put out the necessary amps as they age.  This is why a jump start works, it supplements the weak battery and overcomes the poor contacts with lots of amps.

 

Battery connections and fusible link connections can cause issues too.....

 

And what you say about jumpstarting is backwards.  Remember, for any given load (watts)......if the volts go down....the amps required go up.

 

It's actually supplementing with more Volts which decreases the amount of amps consumed by the load.......making it so amperage is low enough to be passed by the weak connection.

 

If all connections, and the battery are good.....and you've replaced the starter (could have done just contacts).......And it still sometimes won't start....It means the ignition switch is weak..........I'd install a relay for the start circuit.

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Just installed the relay today. This is exactly what I did.

 

Seems to be working fantastic. The ever present delay between the time the key is turned to "start" and the starter actually engaging is gone. Instantaneous engagement now.

 

85,86,87,87A, and 30 are standard terminal designation for bosch style 4 or 5 pin relays.

 

85 and 86 are the low amp "trigger" terminals.....basically a + and - to activate the relay. In this case would ground 85 and run the original starter wire to 86.

 

30 is the "in" for the High amp side......so in this case the battery power.

 

And finally 87 is the "out to load" of the high amp side. So in this case output to starter.

 

87A would be the "normally closed" position....not used in this case...

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And I don't think what you're saying about jumping the car makes sense. When two batteries are connected via parallel jumper cable, (positive to positive, negative to ground) the total voltage is still 12 volts. Is the amperage you're increasing.

 

So if you have one battery with 300 cold cranking amps and you hook jumper cables up to another 300 CCA battery, at the end you're getting 12 volts and 600 cranking amps. Not the other way around

 

If you hooked in *series* (bat1 +to load bat1 - to bat2+ and bat 2 - to load) you would get 24 volts and your electrical system would be unhappy.

Edited by l75eya
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I have held the alternator suspect too for that very reason, though after the problem did come back it only happened once, as with the battery that was in there before, the problem was always very intermittent.

 

I don't know :-\ , what I can say is that the alternator in there is only about 4 months old since I put it in. Remanned from auto zone. I have intentions to maxima swap it eventually.

 

The battery in the car I can't say off the top of my head, but I know for sure that it's higher rated than the battery the car calls for. Its not the right battery and it's huge. Came from a 93 Audi 90. Had to start that big i-5 cyl heh

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And I don't think what you're saying about jumping the car makes sense. When two batteries are connected via parallel jumper cable, (positive to positive, negative to ground) the total voltage is still 12 volts. Is the amperage you're increasing.

 

 

 

You are not getting it. 

 

I realize that the the sytem is still a "12v" system......But if you watch what happens to votage during cranking it drops when the AMP capacity of the battery is reached, it drops.....a good battery slightly....a bad battery will drop below 9v.......  By increasing the available Amps.........you are keeping the volts higher even during high amp draw.

 

Also......If you are hooking up to a running car....the voltage of that car will be more like 13.5.....which raises the whole system slightly.........Let's do some math.

 

Lets say the starter solenoid draws 10 amps at 12v  (might be less or more...just a round #)

 

10 Amps at 12v = 120 watts....so that is our load amount.....120 watts.

 

So let's play with volatge a bit....If we bump the volts to 13.5

 

120 watts @ 13.5v = 8.889 Amps........less amps required on the ignition circuit.

 

But if we dropp the voltage....even to just 11, let's se what we get....

 

120 watts @ 11v = 10.9 Amps.........almost an amp more needed of the ignition circuit.

 

This is why the jumpstarting works......You are dropping the require amps on the circuit by increasing the voltage to 13.5 and keeping it from dropping under load by having a bigger "reserve" of Amps behind it.  the circuit can pass 9 or 10 amps....barely......but not 11 or more (not true numbers for starter just estimate)

 

This is also why the relay works.......using the Starter circuit to power a relay (20watts or less) rather than the solenoid directly.  Keeps the load on the circuit down massively.

 

20 watts @ 12v = 1.66 amps or less.

 

So if you have one battery with 300 cold cranking amps and you hook jumper cables up to another 300 CCA battery, at the end you're getting 12 volts and 600 cranking amps. Not the other way around

 

 

A load will only pull what it needs.....you can put a 10,000 amp battery in....and the starter will still only pull the same ~250/300

amps.....you cannot increase the Amps to the starter.....only what's available for it......you can lead a starter to current......but you can't make it work any harder.

Edited by Gloyale
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You are not getting it. 

 

I realize that the the sytem is still a "12v" system......But if you watch what happens to votage during cranking it drops when the AMP capacity of the battery is reached, it drops.....a good battery slightly....a bad battery will drop below 9v.......  By increasing the available Amps.........you are keeping the volts higher even during high amp draw.

 

Also......If you are hooking up to a running car....the voltage of that car will be more like 13.5.....which raises the whole system slightly.........Let's do some math.

 

Lets say the starter solenoid draws 10 amps at 12v  (might be less or more...just a round #)

 

10 Amps at 12v = 120 watts....so that is our load amount.....120 watts.

 

So let's play with volatge a bit....If we bump the volts to 13.5

 

120 watts @ 13.5v = 8.889 Amps........less amps required on the ignition circuit.

 

But if we dropp the voltage....even to just 11, let's se what we get....

 

120 watts @ 11v = 10.9 Amps.........almost an amp more needed of the ignition circuit.

 

This is why the jumpstarting works......You are dropping the require amps on the circuit by increasing the voltage to 13.5 and keeping it from dropping under load by having a bigger "reserve" of Amps behind it.  the circuit can pass 9 or 10 amps....barely......but not 11 or more (not true numbers for starter just estimate)

 

This is also why the relay works.......using the Starter circuit to power a relay (20watts or less) rather than the solenoid directly.  Keeps the load on the circuit down massively.

 

20 watts @ 12v = 1.66 amps or less.

 

A load will only pull what it needs.....you can put a 10,000 amp battery in....and the starter will still only pull the same ~250/300

amps.....you cannot increase the Amps to the starter.....only what's available for it......you can lead a starter to current......but you can't make it work any harder.

 

This is nonsense.

The load represented by the starter is not a constant wattage at varying voltages.

 

Everything follows Ohms Law,V=IR

If the applied voltage drops and the starter resistance remains the same,the current must drop also.

Therefore the wattage (VI) drops too.

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This is nonsense.

The load represented by the starter is not a constant wattage at varying voltages.

 

Everything follows Ohms Law,V=IR

If the applied voltage drops and the starter resistance remains the same,the current must drop also.

Therefore the wattage (VI) drops too.

 

That law uses resistance meaurement.....which is related to the Watts consumed.....

 

You must also rememeber Watts law.......Watts= Volts x Amps.

 

Think about a headlight.  If it's a 55w light......it will use 55w....always......but if the voltage is dropped (which is what resistance does) the AMPS required to run said bulb goes up.  When the Voltage goes low enough...the Amps exceed the capacity of the wiring.....and the connector melts.......Same thing happens with poor contacts at the bulb since the resitance causes a volt drop at the bulb......increasing the load...further burning up the connector.

 

If this isn't true......then tell me how to make a light bulb consume any more or less watts.......without adjusting the voltage.

 

 

Let me put it a different way........If you can "give" more amps to something than it's watts rating (True, that is related to the resitacne of the windings in the motor) require........then why isn't every piece of electical componentry in the car fried by the 500+ amps available at the battery?.....

 

Answer: Each and every item will always only draw the amount of amps it requires based on it's Wattage.  That is why electric motors give an Amp rating spec. @ a given voltage.....cause if the volts go up or down it changes the Amps in the opposite direction.

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Your 55 watt headlight is no more of constant wattage load than the starter.

If you drop the applied voltage,the current will go down not up like you claim.Try it.

 

Headlights are not a great example because thier resistance will change w/temperature and therefore w/voltage/current changes as well.

That 55 watt lamp will draw a lot more than 55 watts for the first few microseconds after it is turned on  before the filament heats up and increases resistance.

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  • 10 months later...

You are not getting it. 

 

I realize that the the sytem is still a "12v" system......But if you watch what happens to votage during cranking it drops when the AMP capacity of the battery is reached, it drops.....a good battery slightly....a bad battery will drop below 9v.......  By increasing the available Amps.........you are keeping the volts higher even during high amp draw.

 

Also......If you are hooking up to a running car....the voltage of that car will be more like 13.5.....which raises the whole system slightly.........Let's do some math.

 

Lets say the starter solenoid draws 10 amps at 12v  (might be less or more...just a round #)

 

10 Amps at 12v = 120 watts....so that is our load amount.....120 watts.

 

So let's play with volatge a bit....If we bump the volts to 13.5

 

120 watts @ 13.5v = 8.889 Amps........less amps required on the ignition circuit.

 

But if we dropp the voltage....even to just 11, let's se what we get....

 

120 watts @ 11v = 10.9 Amps.........almost an amp more needed of the ignition circuit.

 

This is why the jumpstarting works......You are dropping the require amps on the circuit by increasing the voltage to 13.5 and keeping it from dropping under load by having a bigger "reserve" of Amps behind it.  the circuit can pass 9 or 10 amps....barely......but not 11 or more (not true numbers for starter just estimate)

 

This is also why the relay works.......using the Starter circuit to power a relay (20watts or less) rather than the solenoid directly.  Keeps the load on the circuit down massively.

 

20 watts @ 12v = 1.66 amps or less.

 

 

A load will only pull what it needs.....you can put a 10,000 amp battery in....and the starter will still only pull the same ~250/300

amps.....you cannot increase the Amps to the starter.....only what's available for it......you can lead a starter to current......but you can't make it work any harder.

Thank you this explains why my fuse keeps blowing. Not too much current, ive got bad connections causing too many amps. Perfect explanation
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