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Hey guys,

Got a problem with my Power FC. When I turn the key on, the ignition relay clicks on and off repeatedly (at about 5-10 Hz). As such I have no ignition and the car won't start. Any Ideas??

I have a RB25DET engine and the car runs fine on the standard computer.

Cheers, Ryno

Edited by Ryno
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so you have put the stock back in since it started doing this and it ran fine? was going to say it could've just been battery but if it starts fine then it would have to be in the pfc. easiest way would be to go to where you got the pfc and get them to come out and hear what the car does. then stick the stock ecu back in and start it. then they can't say that there is nothing wrong with the pfc.

here's that in simple terms, in case you got lost, cause i nearly did and i wrote it.

go to shop.

go get staff.

put pfc in and try to start car - click click, won't start.

put stock ecu back in and start car.

if you haven't tried starting the car with the stock ecu then it is simply a flat battery. the cold weather kills batteries. they can work one day, and be dead the next morning when you hop in to go to work.

Edited by mad082

something internally is fried, as others have said.

do you have the hand controler? youll probably see garlbed characters on the screen. i had this problem with mine from some dodgy wiring experiments. resoldered the burnt track and all was good after that

ECCS relay output most likely no going to earth. This is from a fried chip. Can be fixed. i have fixed a few. do a search heaps of info on how to repair. Pin 40 on my GTR PFC ECU. Anywho that out put should earth when the ign is on.

this might help explain why the fuel relay isn't getting any power .. as i believe its fed via the ECCS

might have to bribe you with a case one day to have a look MAtt :(

ECCS relay output most likely no going to earth. This is from a fried chip. Can be fixed. i have fixed a few. do a search heaps of info on how to repair. Pin 40 on my GTR PFC ECU. Anywho that out put should earth when the ign is on.

I sent the Power FC back to Japan, and they've said there's no problem with it... I've had a look inside and can't see any burnt tracks.

something internally is fried, as others have said.

do you have the hand controler? youll probably see garlbed characters on the screen. i had this problem with mine from some dodgy wiring experiments. resoldered the burnt track and all was good after that

I do have a hand controller, sometimes it freezes on the Apexi Logo (while the ignition relay is clicking away), and other times it goes into the menu, but tends to freeze up after about 30 seconds.

I haven't seen any garbled characters on the screen.

Hey mate, this is your lucky day. I had exactly the same problem as yours. I have a 94 r33, When I bought my Pfc we could not get the car to start. But with the standard comp, the car started with no probs. The thing is your car is running on diagnostic mode. Meaning that someone put it on diagnostic mode and did not re-wire it back to normal mode. Take your car to someone who knows how to wire the comp and try fitting on the Pfc after wiring it back to normal mode. It should start straight away. :(

Edited by str8g

I haven't tried as yet to sort this problem out yet but I have tried at least 5 different pfc's in my car and have had this problem everytime yet they work fine in friends cars. Sometimes they will work but rarely. A few times when they have powered up I have tried to reset to factory settings but it won't.

I think it is just the wiring of my alarm. Check out the post below as I think this is where my problem lies, maybe your too? The earthing of the eccs and coil relay seems to be cruicial. It appears both earths for these relays need to go to pin 16 for the saving function to work, maybe stop it from carrrying on too.

http://www.skylinesaustralia.com/forums/in...opic=109187&hl=

good luck with it.

powerFC Faq shows how to correct ECCS wiring thanks to some guys from here. it covers what wires need to be in tact and a diagram. with it setup incorrectly you are likely to encounter what you are seeing on the dreaded read only PFC mode where any changes you make are lost when u power the car off

im chasing the same problem on a buddies car where we were trying to take pictuarz to prove the rb25 pfc works on a rb20, it works but we are experienceing simmilar symptoms such as the read only bit.

it all comes down to the wiring, since you have a rb25 in a r32 it had to be rewired, but it is wired in a way that it isnt exactly as nissan had designed it; it works but the pfc shits a brick when it tries to figure out whats going on...

paul, looks like that wiring diagram you have it spot on, gonna have to give it a go when i hack my loom apart to rewire it.

I have heard of this before actually but it was like 2yrs ago, it was i wire that was shorted cut or had been joined in somewhere it wasnt sposed to be..... gl dude it may take a while. check a wire hasnt melted under the engine bay or something like that aswell as in your car.

The 2 easiest things to check (seeing as it's an engine swap) are that pin 45 is getting a switched ignition source off the dash plugs. (all the other wiring from pin 16 to the eccs and ign relays and power feeds back to the ecu should be untouched as it doesn't need to be modified at all during the conversion from memory).

And that the constant power to the eccs and ign relay in the foot well is up to the job of powering the coils. A direct 20amp wire off the battery will solve this one if you can't find a decent gauge wire in the r32 loom to power off. I think this will be the cause of your problem as the pfc seems to suck a bit more juice than the stock ecu for some reason.

While you're in the footwell, check that 58 (i think it is) is getting a constant 12V supply as well. Thats your battery back up.

Wow,

Theirs nothing wrong with you'r computer, i'm almost 100% sure that the computer is not getting 12vlts, which will not run the FC, as i have seen in previous experience the Standard ecu only needs 8vlts to run the car :O

You will have to run a new wire from you'r fuse box, which is on ignition switch other wise if you go direct from battery it will be on all the time.

Wow,

Theirs nothing wrong with you'r computer, i'm almost 100% sure that the computer is not getting 12vlts, which will not run the FC, as i have seen in previous experience the Standard ecu only needs 8vlts to run the car :O

You will have to run a new wire from you'r fuse box, which is on ignition switch other wise if you go direct from battery it will be on all the time.

I have already run a wire from the Battery directly to the Power FC, so the Power Supply isn't the problem.

It looks like my next step is checking the ECCS wiring (As BHDave says, pin 45), otherwise I'll be checking all my wiring for a broken one! ;) And as sinistagtst pointed out, it will probably take a while.

I'm just fortunate I can still run the car fine on the standard computer.

if you go direct from battery it will be on all the time.

Thats the point. Constant power to the input side of the relay, ecu trips relay, power to the ecu.

If you run it through another switched ignition you won't be able to save settings on the fc as it won't be able to maintain power for the second or so after the ignition is switched off.

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