Request for help: diagramming a relay

[BailOut]

Originally Posted by Tamago

30: common to battery 12V
87: common to "stereo power wire"
85: common to "starter solenoid 12V"
86: common to GROUND.
87a: not used

so, only when the starter solenoid is engaged, the relay is in operation. because you're using 87 (NO contact) you won't be powering anything when the key is turned off. and because you've hooked 30 to "constant" your ACC circuit will be backfed power directly from the battery during the "start" cycle. since the ACC circuit does not power high-draw items such as the windows or AC or fan or defrosters, you should not have an issue with battery draw during the "start" cycle.

sound good?

also, this can all be done right at the radio (no need to run a feed from the battery itself)

Ahh - now we're getting somewhere. Thanks! That sounds like a solid idea.

Though it can all be done "at the radio" where would I tap into the "starter solenoid 12V" line? From the engine compartment, I presume?

[Tamago]

Originally Posted by BailOut

Ahh - now we're getting somewhere. Thanks! That sounds like a solid idea.

Though it can all be done "at the radio" where would I tap into the "starter solenoid 12V" line? From the engine compartment, I presume?

i don't know the actual yaris wiring diagram so i won't say what i think is the obvious answer (at the ignition itself). for all i know the yaris uses sinking switches instead of sourcing to send the "start" signal.

[CTScott]

How about just eliminating the ACC cut relay and jumping the output contact terminals? The service manual says that its purpose is just to keep the clock and meter from flickering during cranking.

You could use a jumper wire with male spade terminals. Jump 3 to 4.





ACC Cut Relay.jpg

[BailOut]

Originally Posted by CTScott

How about just eliminating the ACC cut relay and jumping the output contact terminals? The service manual says that its purpose is just to keep the clock and meter from flickering during cranking.

You could use a jumper wire with male spade terminals. Jump 3 to 4.

That sounded like a great and simple idea but it did not work. I jumped 3 to 4 to no effect. The interesting thing is that the clock works just fine (no flickering) with or without the ACC cut relay or 3-4 jumper in place.

Thanks for trying, though. Tomorrow afternoon I'll try wiring in a relay.

[CTScott]

Originally Posted by BailOut

That sounded like a great and simple idea but it did not work. I jumped 3 to 4 to no effect. The interesting thing is that the clock works just fine (no flickering) with or without the ACC cut relay or 3-4 jumper in place.

Thanks for trying, though. Tomorrow afternoon I'll try wiring in a relay.

Try 3 to 5 then. I wasn't sure if the NO or NC contacts were being used.

[BailOut]

Originally Posted by CTScott

Try 3 to 5 then. I wasn't sure if the NO or NC contacts were being used.

I thought of the same based on the diagram you attached but pin 5 isn't used in the ACC cut relay's socket. It's an empty space.

[CTScott]

Originally Posted by BailOut

I thought of the same based on the diagram you attached but pin 5 isn't used in the ACC cut relay's socket. It's an empty space.

OK. That makes sense - The EWD shows 3-4 being the contacts.

If you put a voltmeter on the power wire, do you actually see it still cut out with the jumper in place (or just sag to below 12V)?

Looking at the EWD, with that jumped, power should definitely still be applied to ACC during cranking.