bad6as

iTrader: (17)

Well im redoing some of the wiring in my car and getting rid of some stuff that dosent need to be in there.

when i turn my key on it powers up the (key on power relay) that relay then powers my fuse block and also powers my other relay that turns on my (pcm relay) which turns my pcm on.

my harness has one wire to turn on the pcm. whats the best way to give that wire power.

from ignition switch to pcm
ign switch to relay to pcm
from key on fuse block to pcm

Andy1

Too much current to run through the ign switch. I went with the ign switch to relay to PCM on mine. And yes, you need to fuse the power feed.
Andy1

bad6as

iTrader: (17)

Ill use the single, key on 12v wire off the ign switch and split it and trigger the pcm relay and 12v key on relay for the fuse box

tsnow678

iTrader: (3)

I thought the PCM needs to stay hot at all times for the memory. I know there was one wire that was a keyed 12v and one that was hot all the time on my setup.

bad6as

iTrader: (17)

Right mine to. I'm talking about the keyed power.
I'm thinking of just using the key on relay to power the fuse box and then go from fuse box to pcm

Pocket

iTrader: (22)

Ditch the PCM power up relay and stick to just the IGN relay powering the fuseblock

bad6as

iTrader: (17)

So power the pcm off the fuse box. And the fuse box is powered to key on relay.
What size fuse should the pcm use

bczee

iTrader: (12)

Just remember that the PCM needs to types of power source.. a) Constant +12volt and b) Key/IGN +12volts.

Look at the fuse box or chart that usually is on the lid of the fuse box.. that would tell you what is the fuse AMP size to use.

And as everyone agreed, the Key/IGN should power a relay that will feed power to the rest of the fuse box fuse and relays.

ShawnQ

Thread revival from the dead!

Pocket, I sent you a PM about your schematic above...but it may help others in the future.

What size wiring do I need from my battery to my IGN relay, battery to PCM fuse, and battery to fan relay?

I know fans typically draw quite a bit. I guess I'm concerned about all of the fuses (except the PCM fuse) getting their power from the IGN relay.

Everything I've read has shown 14AWG is sufficient, so that's what I bought (and terminals to fit). But, when I researched 14AWG (after the fact), 20AMPS is on the limit for it.

Am I safe running 14AWG from my Battery to the IGN relay?
Am I safe running 14AWG from my Battery to the PCM fush Batt+?
Am I safe running 14AWG from my Battery to the Fan relays?

I am basically setting up my fuse box EXACTLY like the schematic. The only thing I'll do differently is run a single speed fan (if I even run a fan, still not sure, I may use the clutch fan).

Thanks,
Shawn

Pocket

iTrader: (22)

Ill type it out again for everyone's benefit

Everything from the batt is 12ga
The jumper connecting the L/R strips is 12ga
All relay high power in/outs (30,87) are 12ga
AC is all 18ga
Rest is all 18ga

14ga is not enough to run the engine and power the fuseblock

Just for reference, stock used 16ga in/out on the FP relay. I use 12ga for consistency, plus alot of aftermarket pumps will overload 16ga cable such as the bosche 044

ShawnQ

Pocket,

Thanks for your info and your time. Your posts are invaluable to us newbs.

I went out and bought 12awg while I waited for a reply as I assumed the 14awg was too little. I couldn't make the 10awg work well (terminal ends wont hold it well, so I didn't even try to solder it).

Thanks again!
Shawn

EFIHARNESS

In the above circ there is no protection for the fan motors (stalled motor=burned wire or worse). Steve

ShawnQ

Would a simple inline fuse on the + side of the fan motor solve this issue?

ShawnQ

I've got another question:

My 6L80E has a battery (+) wire. If I need constant Battery + voltage, would I be safe connecting this in line with my PCM/Fuel relay fused battery (+) with the 20AMP fuse?

I'm not sure if the 4L60/80 required a Battery+ for their TCM...but my 6L80 has it (as far as I can tell from the schematics).

Thanks
Shawn

Pocket

iTrader: (22)

Protect it however you want. Higher amp loads like this require a maxi-fuse which doesnt fit the little holder everyone uses. Plan B is a fusible link which should be common knowledge. The drawing is an aid, not a production schematic so things are left out