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IDS_Bill
06-30-2021, 08:25 AM
I'm chasing a parasitic drain of 0.8 Amps in my 67 Camaro with an LS3. Removing certain fuses, I see .2 drops across a couple of circuits in my AAW wiring harness and am wondering something simple:

I have relays powering windows, trunk release, etc. Does a relay consume current when not in use if hooked up to the battery (vs ignition)?

Thanks for any help,

Bill

dontlifttoshift
06-30-2021, 09:09 AM
A relay will only draw current when the coil is energized. Terminals 85 and 86 are the coil connections.

IDS_Bill
06-30-2021, 10:44 AM
A relay will only draw current when the coil is energized. Terminals 85 and 86 are the coil connections.

IF I have batt power going to the 30 pin with the 85 pin grounded, I am finding that it draws about .2A. Is this consistent with how they should operate?

Hotwire
06-30-2021, 12:01 PM
Is this a 5 pin relay? Is there a pin 87A? If so, that's where your drain is.

When a 5 pin relay is de-energized pin 30 makes contact with 87A. It's normally closed.
When any relay is energized pin 30 makes contact with 87. It's normally open.

Found this image doing a quick search. If you can make it out you can see pin 30 is normally connected to 87A until the relay is energized, then it disconnects from 87A and connects to pin 87.

190048

*EDIT* No, that is not how a relay works. Pin 85 is for the coil of the relay, only other connection to pin 85 is 86, that's the coil

IDS_Bill
06-30-2021, 12:13 PM
Is this a 5 pin relay? Is there a pin 87A? If so, that's where your drain is.

When a 5 pin relay is de-energized pin 30 makes contact with 87A. It's normally closed.
When any relay is energized pin 30 makes contact with 87. It's normally open.

Found this image doing a quick search. If you can make it out you can see pin 30 is normally connected to 87A until the relay is energized, then it disconnects from 87A and connects to pin 87.

190048

*EDIT* No, that is not how a relay works. Pin 85 is for the coil of the relay, only other connection to pin 85 is 86, that's the coil

Makes sense. I'll check the 87A. They are 5 pin but I don't think there is anything connected to any of the 87a pins. Thanks for the clarification.