Hi All

Wondering if anyone here can help with an issue my friend is having with his 2011 DB9 Volante Automatic. I'm more of a Porsche guy so don't know any specifics on the car except that... and the V12 sounds amazing! Anyway he came over to scan his check engine light and turns out its an o2 sensor code. But I did notice two other weird issues:

1. When you turn off the car everything seems fine and then a minute or so later there is this rapid clicking sound coming from passenger side engine bay (sounds like it anyway) and the fan starts to go on. Any ideas what this is? Maybe a relay clicking?

2. It takes a long time to crank the engine to get it to start. I noticed it right away and he said its always been like that since he bought it 6 months ago. He said most times you have to just crank a bit (push the key in), stop, then crank again and it starts. Sure enough that procedure works. Any ideas?

The only thing that he has done is changed the battery recently to an interstate battery, The old one was already an aftermarket replacement and not holding charge. Car only has 31,000kms so around 20K miles.

Any help is greatly appreciated!

 

Hello there, I found your post when starting to diagnose a coworker's 2009 V8 Vantage earlier this year. I figured I'd come back and post what I found for you and anyone who does the same.

For background, the V8 Vantage and the DB9 share a ton of electrical parts with each other, as well as a ton of other Volvos/Fords/Jaguars etc. from the era.

I noticed the PCM relay in the underhood fuse box was clicking, and that the clicking and fan running would go away once the relay was removed. I disassembled the underhood fuse box and found that there was a large patch of copper oxide-colored staining on the inside of the bottom plastic shell of the box.



The coworker bought a new fuse box, and upon swapping it out all the issues were resolved. The part number on the fuse box was 4G43-14A173-AF, it was manufacturer by Lear and used in both the V8 and V12 Vantages, as well as all DB9s. They're available new for about $500 dollars as of writing this in 2024.



https://www.scuderiacarparts.com/part/181147/astonmartin/4g4314a173af/engine-bay-fuse-box.html

I was not satisfied with just swapping out the part, and with the coworker's permission cut the old board apart to find the reason for the failure. It appears that either water pooling or heat buildup causing condensation created water damage and corrosion on the corner of the board, and that once the corrosion started, the insulative layer peeled off the board and caused shorting between circuits.







Because of this, I would not recommend replacing with a used fusebox, as it seems to happen to all of these eventually.

Best of luck, hope you were able to keep and fix the car!

-E