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Discussion Starter · #1 ·
Have posted this one a while back, but thought some new thoughts might be about...

My APC solenoid gets toasted every time the fuse is replaced. To be more explicit, the fuse blows that supplies the APC solenoid but not before the fine coil wire in the solenoid has taken too much current and has melted. This is pretty expensive as a new solenoid has to be procured every time this happens.
I gave up trying to find the cause after checking the wiring between the solenoid and ECU and finding nothing wrong (No obvious shorting to earth).
Could the ECU be at fault? (As I understand it the ECU grounds the negative side of the APC solenoid coils in a pulsating cycle, alternating from the open to closed sides at 90Hz - could one side be stuck permenently energised causing the coil to overheat and self destruct?)

Has anyone had this problem and overcome it?
All help would be appreciated.

Cheers

Nick.
 

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It would seem to me that if you are replacing the solenoid and the fuse each time this happens; then something in the ECU must be causing the condition. As you stated; perhaps it is grounded on one side. I would think there must be a way of testing with a meter for a direct short. Also could be something with the touching the board somewhere as I believe the board has an isolated ground. Maybe someone else can give you some help with ECU diagnostics

Regards,
John
 

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Hi mate,this is a bit of a common fault going back some years ago,people were changing the
BPC solonoid because of this fault but the problem was the failed BPC valve damaged the ECM so you would blow the new valve.
Ive repaired this problem on two cars and it required the ECM and the valve,
This is one to watch out for as people tend to forget the knock on affect of the original faulty BPC valve.
Hope this helps and in future put a 21 watt buld in series to prevent further damage when testing.
 

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Discussion Starter · #4 ·
Thankyou for your reply.
I'm now fairly confident of fixing this fault, but only with a new/ secondhand ECU
. Any ideas where a reasonably priced Aero ECU could be sourced or is a straight upgrade the cheaper/far better option?

Nick.
 
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