Auto tC Turbo FIC Battery Drain Fix
 

EDITED


I see a lot of people with this issue, including myself at one point, and no one has gave a definite answer as of how to do this. This is for Auto TC owners running the AEM FIC who are experiencing battery drain during shut off. This is caused by the FIC leaving on a few of the car's sensors after you turn the car off. Usually people say their hear a "whine" or a "hum" coming from the engine bay. This has worked for me, and havent had the problem since. Here we go....

Tools needed:
-wire stripper/crimpers
-electrical tape
-18g wire (about 10 ft)
-solderless crimp connectors
-4 pin relay
-solderless female connectors
-butt splice

Lets start off by looking at what wire we are going to be messing with.
http://i40.tinypic.com/ivhdvb.jpg
http://i43.tinypic.com/25rh1l5.jpg
http://i39.tinypic.com/ezqqrl.jpg

This is PIN 5 off of the 22 pin connector on the FIC harness. (wires facing you).

Pick up a 4 pin relay at your local auto parts store:
http://i40.tinypic.com/2h6525d.jpg

Take note of the pin numbers on the relay.

1) Disconnect your battery

2) You are going to cut Wire 5 (black) in half on the FIC harness, leaving about 4 inches of room from the connector.

3) Cut off about 10 inches of wire from your 18g wire, and crimp one side to Wire 5 of the connector side of the FIC harness, and crimp on a female connector to the other side and run it to pin 87 of the relay

4) Cut off another piece of wire and and repeat step 3, only run Wire 5 from the harness end to pin 30 of the relay.

5) Cut off about 5 feet of 18g wire, crimp on a female connector to one end and connect it to pin 85 of the relay. Run the other end of the wire to the orange wire under the steering column (ign wire) and connect useing a butt splice. As seen in picture below:
http://i43.tinypic.com/66cl6u.jpg
http://i44.tinypic.com/fozwae.jpg

6) Use the last of your 18g wire and crimp on a female connector to one end and connect it to pin 86 of your relay. Run the other end of the wire to any chassis ground, or if you want, you can run it all the way to the battery to the negative terminal. This is where i ran my ground wire, its the bolt in the upper right corner behind the glove box:
http://i41.tinypic.com/1zcl577.jpg

Here is a little diagram that may help.
http://i39.tinypic.com/wwj8yx.jpg

After much trial and error i finally figure it out. I originally thought it was the ignition power to the FIC harness (PIN 16, RED) that needed to be cut off, but after a few days i heard the noise again. So this IS the correct way. If anybody has any questions, feel free to post. Thanks

iv had to do this on a customers car, if i remember correctly I placed the switched side of the relay between the ign relay (pretty much switching the switched side of the ign relay) and found a switched + (ign on) source to power up the coil side of my relay.
now that sounds pretty confusing even to me...lol...so i give you props on the right up brethren...good job!

thank you!

i read that post about 15 times trying to figure out what you meant but now i get it! lol. i dont see a problem doing it that way either, considering their both getting a + connection from different sources, either way. and obviously it works since you did it yourself!

EDITED DIY

i posted this thread up 3 days ago, but didnt realize my problem hadn't completely gone away. somtimes it would shut off, sometimes it wouldnt. so i took all of today to figure out exactly what wire on the harness to relay, and i found it.

Im guessing no one did this yet, but if anyone did, please fallow the NEW/REVISED instructions above and that should take care of it. Sorry for any inconvenience

-steve

You're an auto?

he had an auto and manual tC, he sold the mt tC, both boosted btw lol ^

Yes. I figured an auto was in the picture. I explained to several people over the phone on how do this. I am glad someone has a DIY so I can refer people to that.

Are you sure you splice into an orange wire at the ignition? It looks like you spliced into the yellow one... I see the yellow wire but don't see an orange one

I think its just the flash that makes it look yellow.

Mine looked yellow but from the photo its the same wire it seems... I taped into it and w everything seems fine

Check on the white connector where the yellow/orange wire goes and it should say IGN inline with the wire on the plastic connector. One thing toyota made easy lol

yeah well at least they could do something that makes it easier... i haven't had a chance to check since buttoned everything up but so far my battery drain problem is gone... hopefully it stays that way and i don't have to pull everything apart again.

when you shut off you car, get out and listed under the hood. if its buzzing or whining then its still happeneing. if not, problem fixed!

Yeah I checked for the sound... No more buzzing lol. Thanks guys for all your help. Next will be a turbo timer and eventually a boost controller

have xb2 turbo maybe thats why my battery kept going bad, just bought brand new optima yellow. well if starts to act up again i guess i know what it is.

I did the same thing, our just took longer for the yellow top to fully drain then I was back where I started.

could very well be. theres 2 buzzing sounds. 1 is the throttle body i believe, and the other is a sensor in the transmission. the one in the transmission is VERY quiet. you almost can't hear it, unless your in a closed garage thats absolutely silent.

simple test for ya. when you shut down, unplug the smaller (22 pin) connector, and plug it right back in. if your battery doesn't continue to drain, then you need to install the relay.

has anyone experienced a moving throttle body even after car is in off position because of auto ecu

Cant we just tap into the ignition wire in the FIC harness?

I tapped into the ignition at the steering colum since I already had my turbo timer there... Not sure if the ignition on the fic would work since it seems to need to since the car keying off.