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Discussion Starter #1
Hi guys, havent been here for a while. Sorry for that. I am swedish so I am not so good at technical english, hope you understand my question.

I have a 2007 FJC 2wd with a resently upgrade, URD supercharger st 1.
I have been having trouble with lost batterypower when car sits still. But only sometimes.
Having a ampmeter hooked up I pulled fuses and relays and found the EFI relay being active, no key in and doors locked.
Its pulling about 0,8-0,9 amps.

Only way to set it off is to pull the two fuses ETCS and EFI or disconnect the battery, then the relay stays off.
I have also noticed that even if the EFI relay is off when I park the car, next time/day it can be activated.

So what is activating the relay (ECU apparantly) and when should it be on?
I have the diagram so I can see all the things it is giving power to but I cant imaging these things need to be on when car sits still.Or is there?

I have tryed to disconnect the upgrade ECU provided by URD and driving for a few days with only stock ECU and all was good.
Then connected URD ECU and driving for three days, all good. Then after a few days standing still, relay active again. And power lost in battery wich is brand new 95Ah.

I have talked with URD, tryed to explain but he said he never heard of it before.

Any help and input would be most welcome.

//Per
 

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Discussion Starter #2
To clearify my question.
According to the wiring diagram its the ECU via output MREL that triggers the EFI relay, wich triggers the A/F relay and powers the EFI No.2 fuse.
All in all these things gives power to:
MAF meter
A/F ratio sensor x2
Heated oxygen sensors x2
...and a number of other things.

I just cant imagine these things needs to be on when car is parked, but since it seems to be controlled by the ECU I am not sure.
Anyone got any inputs on this?

The cars has also been harder to start, takes a few secs. on the starter, wich was never before this issue came along.
Could it be because the MAF and A/F sensors sending the wrong info to the ECU when the engine is off?
Could it be related?


I am going to do a another test and drive for a week with original ECU, see if it works, and then plug in the URD box and see if the problem comes back.
If its so I will take it up again with URD.

I was just hoping someone here know anything how this works with these relays, I want to know more.

//Per
 

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(See comments interspersed)

To clearify my question.
According to the wiring diagram its the ECU via output MREL that triggers the EFI relay, wich triggers the A/F relay and powers the EFI No.2 fuse.
All in all these things gives power to:
MAF meter
A/F ratio sensor x2
Heated oxygen sensors x2
...and a number of other things.

I just cant imagine these things needs to be on when car is parked, but since it seems to be controlled by the ECU I am not sure.
Anyone got any inputs on this?

None of these sub-systems should be powered when the engine is not running.

The cars has also been harder to start, takes a few secs. on the starter, wich was never before this issue came along.
Could it be because the MAF and A/F sensors sending the wrong info to the ECU when the engine is off?
Could it be related?

Output signals from MAF, AF, and oxygen sensors would have no affect on keeping the control relays "latched" and not turning off when the ignition is turned off.

800 - 900ma is a grossly excessive parasitic current draw, and will quickly drain the battery as well as ultimately "kill" it from repeated deep discharge. Typical parasitic current draw shouldn't exceed 50ma unless you have an alarm system that is always on standby, etc.

I am going to do a another test and drive for a week with original ECU, see if it works, and then plug in the URD box and see if the problem comes back. If its so I will take it up again with URD.

That should confirm if the excessive parasitic current is due to some problem originating in the "URD box".

I was just hoping someone here know anything how this works with these relays, I want to know more.

It is possible for relays to fail by "sticking" in either the OPEN or CLOSED position, or become erratic as the contacts erode. Are all these relays the original 12 year old parts?
 

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Discussion Starter #4
Thanks FJtest, your answers is just in line with my thoughts. Just wanted to here it from an expert.

To answer your last question:
Yes I think these are the original relays because the car has only 25k miles on it. But yes they are old. On the other hand, everytime I parked since this problem accured I have been checking if EFI relay where active.
One time it was not active when I parked but next day the relay have been activated while car was parked.
Also when you pull the two fuses and make ECU powerless the relays goes off easily and they will stay off even if you power the ECU again. So I dont think its relay related.
All these with the URD box.

I will go on with my ECU testing, stock (boring) vs URD, and see where that leads.

Thanks again man, for taking your time, I'll get back when I got more info.

//Per
 

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Thanks FJtest, your answers is just in line with my thoughts. Just wanted to here it from an expert.

To answer your last question:
Yes I think these are the original relays because the car has only 25k miles on it. But yes they are old. On the other hand, everytime I parked since this problem accured I have been checking if EFI relay where active.
One time it was not active when I parked but next day the relay have been activated while car was parked.
Also when you pull the two fuses and make ECU powerless the relays goes off easily and they will stay off even if you power the ECU again. So I dont think its relay related.
All these with the URD box.

I will go on with my ECU testing, stock (boring) vs URD, and see where that leads.

Thanks again man, for taking your time, I'll get back when I got more info.

//Per
With only 25K miles on the odometer, your relays don't have many actuation cycles on them, and it's unlikely they are the root cause of your problem. Over here in the states, when one is talking about an '07, many of them have 100K and more miles on them.

If you didn't make any other recent wiring modifications, I'd strongly suspect the URD controller.
 

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Discussion Starter #6
Yeah, we will soon find out.
Car is like brand new, sold in Santa Monica 2007. Guy moved to sweden and took his car with him. Sold it in 2013 and then I bought it in 2015, so only two owners before me.
Still got the cover plastics in some parts on the inside panels. Got a load of papers and invoices seens car was new, so its well taken care off.

Not my daily rider as you might suspect.
Petrol is VERY expensive here.

Read you later.
 

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Discussion Starter #7
Hi there. So this is what happened, after some talking with URD I sent the box back to them. They put it in a car to see if the issues I have could be seen.
After about four weeks I got it back and a email saying they havent found anything but he hade replaced something called powertrain adapter board.

And now its working great and it has been for a while now.
So happy days.

Per
 
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