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Power Fc Not Shutting Down

Dioscorides
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Dioscorides Rookie

Dioscorides

Posted
Posted

Hi All,

My mechanic took my R32 GTR to diagnose why my cars battery kept dying (even brand new batteries, were going dead if the car was left sitting for a few hours/days) - he identified that the ECU was the problem, so we pulled it out and sent it off to an auto elec (Injectronics in Hallam, VIC) for testing. They fired it up and everything seemed to be working fine until they tried to power down the unit - which then subsequently proceeded to cycle and start back up everytime. Unfortunately they weren't sure what was causing this fault and thus were are unable to fix the problem - so I'm left with their testing fee's and now need to purchase a new PFC + Map xfer and dyno costs. The initial unit was installed and tuned in the car when I originally bought it but I have been having the problem for a long time and regularly had to jumpstart it if it had been sitting for awhile and only today just managed to figure out what was causing the issue.

So was just wondering if any of you have had any similar issues with your Power FC's? And/or how you managed to work around it? Also i'm somewhat hesitatant now to purchase another PFC as I don't want to lay out awhole bunch of cash to end up with the same problem if it is a common issue.

So if you've had issues with your PFCs that aren't related to dodgey installs or tunes - let us know!

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paulr33 Grand Master

paulr33

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Posted

did your car behave this way with the stock ecu?

there is some information missing i think, it doesnt make sense - why was the battery dying? was there a previous issue/fault?

the powerfc is a bulletproof stand alone replacement ecu for the stock ecu, it does what the stock ecu does

so it's really no different in terms of operation etc. i suspect there is something missing from your info, or your car has been fiddled with by previous owner

if the powerfc doesn't turn off when the car does - ie key OFF and it's still running something says to me the ECCS relay is either mangled/faulty/damaged

when the IGN is cut the ECCS relay should flick and tell the powerfc to save the tune and then power off

STATUS Grand Master

STATUS

Posted
Posted

you should be able to xfer maps without any costs we often do it on the bench tester, its pretty much a 2 min operation. If you cant find the root issue it is pretty simple to rig up a relay that drops the constant power to the PFC so it cant cycle on and off.

We see alot of power fc's (repair a shit load) and yes there are quite a few with silly idiosyncrasies but most are car induced damage not the other way around.

Try the contstant power relay mod, just be aware to bypass it when making changes to the power FC say every time you get it tuned.

Dioscorides Rookie

Dioscorides

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Hi Guys, Thanks heaps for the responses.

Paulr33 - The previous owner installed the PFC so I've unfortunately never had a stock ECU in the car as long as I have owned it, and the problem has been around since I purchased it (but I only noticed it happening if I didn't drive it for an extended period of time). The relay was changed, but the problem persisted - hence why the unit was pulled out and taken in for diagnostics. When Injectronics did their tests they said that the unit would start to power down and then start back up midway through the shutdown proceedure (hence why the battery was being drained as the computer starts to shut down, but then ends up keeping the fuel pump, injectors etc active). This was happening whilst the unit wasn't even in the car on Injectronics test bed (So i'm hoping *fingers crossed* that there isn't any other faults with any of the cars wiring etc that need to be addressed as well). The maps should all still be in tact.

STATUS - what suburb are you located in, I might organise to bring it down for you to look at and/or do the xfer for me. I usually just disconnect the battery manually everytime I park the car - but once I get the car back I can take a better look and maybe setup the relay if all else fails.

Dioscorides Rookie

Dioscorides

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Posted (edited)
do you have a turbo timer. ?

you say this was happening even when the ecu was removed ?

Car does have a turbo timer fitted (Looking inside the cabin at the dash, once the countdown of the turbo timer expires the car looks like it is off - engine shuts down, all dash lights etc turn off) - but my mechanic noticed that after some minutes the pumps, injectors etc turned back on even though the car effectively looks off.

Obviously nothing was going on in the car with the ECU removed - but the auto elecs that had the unit by itself apparently could see the unit firing back up and staying on during the shutdown sequence whilst they were testing it. They could be just saying it, but from the symptoms it makes sense and they don't really have any reason to not tell me the truth (because I'm not purchasing another unit off them or getting any other work done by them).

Thanks heaps for the responses guys, you've all given me heaps to think about and to check once the car gets back! I'll be super happy once she's up and running normally again!

Edited by Dioscorides

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