Wiring for a 4 or 5 pin starter relay

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david58
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Wiring for a 4 or 5 pin starter relay

Post by david58 » Fri Jun 19, 2009 12:42 pm

I am installing a relay part# AR204 that I bought at Napa. It has a mounting bracket made on it. I ran into a small problem the relay is numbered differently and has 5 pins instead of 4. A quick search showed how to wire this relay. Below are diagrams for the 4 pin and the 5 pin. I will add this in the electrical forum as well.

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DesertGuy
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Post by DesertGuy » Fri Jun 19, 2009 1:44 pm

David, if using the 5 pin relay, I'd swap the 30/87 pin assignments, as long as the relay does not have a diode. That way 87A will not be "live" from the power source when the switch is off.

Mario gave me that little tidbit when I was wiring my baja and think it is a "betta" way to wire the 5 pin... IMHO

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david58
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Post by david58 » Fri Jun 19, 2009 2:36 pm

DesertGuy wrote:David, if using the 5 pin relay, I'd swap the 30/87 pin assignments, as long as the relay does not have a diode. That way 87A will not be "live" from the power source when the switch is off.

Mario gave me that little tidbit when I was wiring my baja and think it is a "betta" way to wire the 5 pin... IMHO
87A isn't hooked to anything. I don't know if it has a diode or not.

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Speedy Jim
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Post by Speedy Jim » Fri Jun 19, 2009 4:28 pm

It will work as shown in your red diagram.

85 and 86 can go either way (swapped around) as can 30 and 87.

There is a nice tutorial here:
http://www.eurekaboy.com/f250/relay101.htm

Jim

DesertGuy
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Post by DesertGuy » Fri Jun 19, 2009 10:23 pm

IIRC, the diode can be across the coil 85/86 and would not factor into the 30-87-87A pins, my correction. That being said, continuity with the relay "off" is between 30 and 87A. When the relay is "activated" continuity switches to 30/87.

So if you have a power supply connected to 30 and the switch/relay is "off", power would be to an exposed pin, if left uncovered. Swapping 30/87 would cause power to "dead-end" at 87 and only go to 30 when it is activated... hope that makes sense.

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MNAirHead
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Post by MNAirHead » Sat Jun 20, 2009 7:10 am

Dumb question (for the lurkers) - Are the numbers on most components universal?

Meaning do the Does an 87 mean the same thing for all mfgs etc?

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Post by 2088 bob » Sat Jun 20, 2009 8:56 am

yeah timmy you are right The numbering for most if not all bosch style cube relays is the same IIRC

The recommended practice is to make the 30 pin the input pin for switched power to the load As DesertGuy has already mentioned

Be advised that there is a versions of the cube relay that has two 87 pins that go hot together when the relay pulls up

And i agree with Speedy Jim on the little tutorial link he posted really shows things clearly The cct # 3 is not that good an idea you are asking the load fuse to cover control cct as well The cct would be better served with its own 1/4 amp fuse there is nothing wrong with switching the ground leg thou

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Post by david58 » Mon Aug 17, 2009 11:25 am

Starting Issues

ricroz wrote:Start by cleaning the contact from the ignition at the starter, This often gets grimey or corroded from the harsh environment it lives in:

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You can do the jumper wire test to isolate the problem to the wiring or the starter itself. Make sure the tranny is in neutral and parking brake set!


Some owners choose to add an intermediate relay to help with low current issues:

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Hot, humid air is less dense than cooler, drier air. This can allow a golf ball to fly through the air with greater ease, as there won't be as much resistance on the ball.

2088 bob
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Post by 2088 bob » Mon Aug 17, 2009 12:12 pm

the above is one of the better examples of a pictorial representation of a "starter assist relay" setup i have seen , only change i make ,is to take the feed for the relay, from + battery post instead of the heavy starter feed cable, and "FUSE" that piece of wire

If that chunk of wire shorts to ground some how there will be serious some fireworks

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david58
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Re: Wiring for a 4 or 5 pin starter relay

Post by david58 » Tue Nov 17, 2009 6:16 pm

Image
Hot, humid air is less dense than cooler, drier air. This can allow a golf ball to fly through the air with greater ease, as there won't be as much resistance on the ball.

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Dale M.
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Re: Wiring for a 4 or 5 pin starter relay

Post by Dale M. » Wed Nov 18, 2009 12:56 pm

Just using a 14 gauge wire from ignition switch to terminal 50 on solenoid usually fixes starter solenoid problems.... Never have had need for relay...

Dale
"Fear The Government That Wants To Take Your Guns" - Thomas Jefferson
1970 "Kellison Sand Piper Roadster"

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david58
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Re: Wiring for a 4 or 5 pin starter relay

Post by david58 » Sat Nov 21, 2009 6:01 am

Here is a great explanation of why and how the starter circuit works and why it doesn't work by John S. Henry.
http://thebugshop.org/bsfqstrt.htm
Hot, humid air is less dense than cooler, drier air. This can allow a golf ball to fly through the air with greater ease, as there won't be as much resistance on the ball.

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