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Indy's Ca18det Relay Wiring Instructions

Started by drfts12 · Dec 3, 2006 · 14postsSMF 2010–26

drfts12Dec 3, 2006, 8:44 pm · #1

fuel pump:

30: s12 wire yellow/red under dash (stock s12 fuel pump relay wire)
85: ground
86: IGN on
87: black pink wire

and bam, no need to ground anything else

and yes it is the BIG blue/red/black wire.  
side note: instead of making both the big wires go to pin 87, i just solider them together, and put a separate wire from pin 87 to the 2 wires. (that way, it wont be soo thick on pin 87)
KeithDec 6, 2006, 5:31 pm · #2
drfts12fuel pump:

30: s12 wire yellow/red under dash (stock s12 fuel pump relay wire)
85: ground
86: IGN on
87: black pink wire

Sweet...........thanks.  Now is the yellow/ red fuel pump relay wire on the fat white plug under the dash in the middle...............
posted image

Because I don't have a yellow/ red wire on this one.  There is another white plug up high on the kick panel, right above where the stock ecu mounts at with a yellow/ red wire.....is this it?

Also, is there a way to just bypass the stock yellow/ red wire all together.....and wire up the positive and negative terminals at the pump directly...in conjunction with the black/ pink signal wire off the s13 harness with the aftermarket relay?
drfts12Dec 6, 2006, 7:29 pm · #3

I believe there are 3 plugs under there.  All three of those plugs on mine were cut to access each wire color.  It should be that white plug there.

You can bypass it, and go directly at the pump like inde, but if your car is keyed in the "on" position, the pump would stay on constantly, even though the car is off.  If you use the original wire (yellow/red) method, it would shut off automatically, unless the car is running.

KeithDec 6, 2006, 7:49 pm · #4
drfts12I believe there are 3 plugs under there.  All three of those plugs on mine were cut to access each wire color.  It should be that white plug there.
Are the 3 plugs in the middle, like the one in the pic above, or are they over above the ecu?  
IndecisiveDec 7, 2006, 12:35 pm · #5

the three plugs are over the ECU.  

Remember when you removed the old S12 engine harness?  To get it out of the car, you had to unplug it from the ECCS and then it was plugged into three plugs up inside the dash on the ECCS side.  two white ones, a large and a small, and a black, small.  

as far as the fuel pump goes.  Yes, you can bypass the stock wiring.  But you have to run your own wires through the car.  That's what I did.  I ran new wires through the car.

KeithDec 7, 2006, 1:02 pm · #6
Indecisiveas far as the fuel pump goes.  Yes, you can bypass the stock wiring.  But you have to run your own wires through the car.  That's what I did.  I ran new wires through the car.
As far as bypassing the stock wiring........can you give a little detail as to whats involved, and what goes where?
I assume you ground the pump, from the neg terminal directly, and run another wire from the Pos terminal on the pump to the new aftermarket relay, but what else?  I assume the black/pink wire from the s13 harness comes into play somewhere as well.
IndecisiveDec 8, 2006, 8:40 am · #7

black pink is the signal for the relay

the only other thing is the fuel gauge wire.

KeithDec 13, 2006, 8:35 am · #8
Indecisive.

ECCS Control Unit
30 - fused power
87 - black/white (under MAF) ecu power
85 - ground
86 - ignition on

Ignition
30 - fused power
87 - black/red & blue/red (under MAF) ignition power
85 - ground
86 - black/white coming off ECU Relay (under MAF)

Can someone verify...............
Terminal 86 for the "Ignition" relay, says connect to black/ white coming off ecu relay (under maf). Does this get connected to the same black/ white wire that connects to terminal 87 on the "ECCS" relay?

I missed this when I was wiring it all up....seems like I hooked it to an "ignition on" source like the other relays terminal 86's. I need to go back and verify.
gadget1382Dec 13, 2006, 5:52 pm · #9
nogaroberryit didn;t work for me.  it cranked but didn't fire up and when i turned the ignition off all accessories stayed on...weird...i'm going to rewire the relays and try again

Well i have the same issue.... but my engine runs... if you figue this out... let me know!!

Damn Auto elec obviously didnt wire it up right!
KeithDec 13, 2006, 6:43 pm · #10
gadget1382Well i have the same issue.... but my engine runs... if you figue this out... let me know!!

Damn Auto elec obviously didnt wire it up right!
hmmm, did you tap it into the same black/ white wire as the # 87 terminal on the eccs relay?  Well, maybe Indy will clarify...................
KeithJan 4, 2007, 9:14 pm · #11

Indy's instructions worked for me.........thanks man!

Only thing I did different was wired the fuel pump relay according to Gerry, and I also added a relay for the iacv.

Does anyone know how or what needs to be wired to make the idle bump up when an accessory is turned on....like the headlights, fan blower, etc?

drfts12Jan 27, 2007, 4:13 am · #12
Indecisive
red/black - ignition on (under MAF) ground for original ecu relay
red - 12v constant (under MAF) ecu backup power


I need to ground that red/black wire off the DET harness??
KeithJan 27, 2007, 10:14 am · #13
drfts12I need to ground that red/black wire off the DET harness??
no..........it goes to an "ignition on" source
Van_DentonAug 26, 2014, 3:07 am · #14

Sorry to resurect an old thread but i feel it directly relates to this. When wiring up the suggested way here, does anyone have trouble turning their car off? Does the engine continue to run?
Wiring my ecu relay the factory way with the red/black wire switching earth to the relay, the ecu turns on and off like it should at the key, but the car wont start. However if i just put a normal earth to that pin of the relay and put ign power to the red/black it fires up straight away but then doesnt turn off!! So engine keeps running!
Ive tried 2 different ecus! Both do the same.

So in short when i wire up factory the car doesnt start but ecu turns off at the key. If i wire up like suggested here it starts but ecu doesnt turn off!  Im stuck.