Update on battery drain, need help

Post by **Cpt_Impossible** » Wed Jan 31, 2007 3:30 pm

So I had a .5amp drain on the ecu fuse. I found that whatever wire the ecu power was hooked to had power when the car was off, so I switched everything on it to a wire I knew was a switched power source. That put me down to a .10 amp draw.

I found that the only ecu pins seeing power were the 6 injector wires. I cannot see where they end can anyone help me out here? I dont want to have to rip up the harness on the engine bay side. As far as I can see, all six wires go from the ECU Into the engine harness and into the firewall towards the engine. Is there somewhere where all of these merge? I have tried unplugging any sensor or plug I can find near the fuel rail to see but nothing seems to stop the drain.

Does anyone know where the 6 injector wires from the ECU merge?

Post by **Cpt_Impossible** » Wed Jan 31, 2007 7:52 pm

wrong thread
Modified by Cpt_Impossible at 10:11 PM 1/31/2007

Post by **Cpt_Impossible** » Thu Feb 01, 2007 6:38 pm

Anyone?

Post by **Bluefire** » Thu Feb 01, 2007 7:46 pm

They should individually go to each injector.

Post by **Cpt_Impossible** » Thu Feb 01, 2007 9:03 pm

Well they must somehow be connected. Maybe they share a common ground wire? They all show 12v with the ECU unplugged. If they share nothing in common, they wouldnt all see the same voltage. Does that make sense? Even if they go directly to the injector, somewhere their circuits must all go to the battery to see 12v. My question is: where?

Post by **Darius** » Fri Feb 02, 2007 4:29 am

The injectors should have switched ON power (and not ACC ON because they won't get power when the key is on START to reduce load on the ignition system). The ECU individually grounds each injector wire to get it to fire open. You can have 12VDC at the injector and nothing will happen. If they aren't grounded, there will be no current and technically no drain. Check your wiring harness for where the injectors are powered and you should find the problem with that.

Post by **Sil240** » Fri Feb 02, 2007 4:42 am

Bluefire wrote:They should individually go to each injector.

No, all 6 injectors have the same power lead Pin 109.The injectors are fired individually by their ground leads. 103,105,107,112,114,116

I'm a nerd that I remember those pin #'s. lol

Post by **Darius** » Fri Feb 02, 2007 5:25 am

If I could only remember girls' phone numbers that well. jk I'm whipped, but way back when...

Post by **Cpt_Impossible** » Fri Feb 02, 2007 6:55 am

OK, so the only pins seeing 12v with the ign off are the 6 injectors. There are a few others seeing like 3v but I dont think that that would be enough to drain my battery so fast. So what I should be checking then is where the ECU wires are being switched to ground b/c they might be grounded all the time leaving them on?

Post by **Sil240** » Fri Feb 02, 2007 7:21 am

http://www.rb20det.com/ecupinouterror.html

Don't remember what's supposed to have power when the key is off.Check out the pinouts and do you have the R32 All engine FSM???You need it!!!!!

Post by **Cpt_Impossible** » Fri Feb 02, 2007 8:26 am

Ya i have the FSM for the R32

Post by **Cpt_Impossible** » Fri Feb 02, 2007 8:31 am

So looking at the FSM, there is one pin listed as injector ground. Should this be grounded at all times and the ecu itself switches which injector goes to it?

Pin 116 is listed as injector ground

Post by **Cpt_Impossible** » Fri Feb 02, 2007 8:33 am

Scratch that, 107, 108, and 116 are all three listed as injector ground. I am assuming they fire 2 at a time. These wires should all be grounded all the time?

Post by **Cpt_Impossible** » Fri Feb 02, 2007 8:43 am

107,108, and 116 all show zero volts which is good. They are all black with a red stripe and all go to the brown plug in the harness. Seems to be some sort of grounding plug as all thr grounds seem to go there. None of the wires there show any voltage and all show 0.02 ohms of resistance with the chasis. So the gounds seem to check out just fine. so now I am back to square one.

Post by **Sil240** » Fri Feb 02, 2007 9:40 am

Yeah no voltage is a good thing!!!!That was my problem I had voltage on them.But your car runs so your golden.

Look at the RB20DET pinout sheet, print it out and start testing with the key out.

Then figure out what has voltage and if its supposed to. I don't really know what's supposed to or not, but if you can't figure it out, post up what DOES have voltage. Do you have any shorts???That may cause you battery to die out.

What other eletrical things do you have in the car?? Check them as well.

Post by **Cpt_Impossible** » Fri Feb 02, 2007 5:23 pm

OK, I reprobed all fo the pins, the ones seeing power are:4 2.6v (Nothing listed in diagram)7 .02v Tachometer Speed Signal16 7.3 ECCS Relay18 2.5 Fuel Pump Relay45 2.5 Ignition Switch58 12v Battery Power Supply101 12v Injector103 12v Injector105 12v Injector110 12v Injector112 12v Injector114 12v Injector

Should my battery power Supply be on all the time or should it be switched? If it should be switched then I can do that no problem, But I would think that the ECU would need some sort of power coming in when the car is off.

Post by **Cpt_Impossible** » Sat Feb 03, 2007 2:10 pm

anyone know?

Post by **Cpt_Impossible** » Thu Feb 08, 2007 8:51 am

does anyone know if pin 58 should be seeing 12v with the ignition off or if it suposed to be switched?

Post by **Darius** » Thu Feb 08, 2007 1:39 pm

I'm pretty sure battery power (pin 58) is constant 12V for ECU memory. I'm telling you. Trace your injector power wire back to where it was wired into your harness. It is also wired into constant 12V power when it should be on switched 12V power. Verify that first.

Post by **Cpt_Impossible** » Thu Feb 15, 2007 1:10 pm

Update:

I tried undoing the pin 58 battery power where it had been spliced previously and it didn't help at all. I then went after pin 16, the 7v drain. Pin 16 is the ECCS relay. It is an orange wire that goes into the two relays' harness, splits into two orange wires and goes to both relays. I looked at the FSM, and it was suposed to go to both so I played with it a bit. I seperated the three wires and tried all combinations of them. what I found is:

if the wire from the ecu goes to just one (either) relay, there is no drain, it is only when the two relays are in contact taht the drain occurs. 0.7amp drain if the two wires touch without the ecu and 0.10 if all three touch.

The plan now is to splice the ecu wire to just one relay and make a switch that connects the second relay when I want to use the car. Kill switch and problem solved at the same time.

Post by **Cpt_Impossible** » Thu Feb 15, 2007 7:10 pm

Update:

So I went to schmuchs and bought a switch and a nice mount for it and all and drilled a hole in the back of the DIN pocket. Got it all set up and found something odd. When the car is off it acts normally, led lights up when switch is on and turns off when switch is off. The drain from the battery and ecu fuse both drop to zero when it is off so problem fixed. The odd thing is that the car starts reguardless of switch being on or off and once the car starts, the power to the switch goes away so it seems it would have been best to just clip the wire and be done. We will see if i find any problems though but I shouldn't seeing as the wires are cold when the ignition is on.

Update on battery drain, need help

Update on battery drain, need help

Re: Update on battery drain, need help (Cpt_Impossible)

Re: (Cpt_Impossible)

Re: (Cpt_Impossible)

Re: (Bluefire)

Re: (Sil240)

Re: (Cpt_Impossible)

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