P0315 Crankshaft Position System Variation Not Learned Read

[Chopdogs]

Hi All

I have a P0315 fault on my 2012 Vantage V8S

Other than a trip to the dealer, does anyone have any idea how to clear this?

A scan on the net shows that it could be cleared by:

1/ Using an OBD tool with "relearn" capabilities and then revving it until it hits the fuel cut off point

2/ Using a "coast down" procedure - taking it up to 70mph and allowing it to coast down to 40mph and repeating a further two times

Does anyone have any experience of either of these working?

Thanks


J

[Al 450]

Do you have any other fault codes and is the MIL light on? It could indicate a faulty crankshaft sensor but likely you'd have rough running or no running if so. The MIL will clear within 3 drive cycles if the fault does not recur then the DTC will disappear from memory after 40 drive cycles. Alternatively you could buy a cheap OBD reader and plug that in to clear it yourself.

If you also have a P1000 code then it may help to do the misfire monitor coastdown which is a) warm the car up for at least 200 secs and b) 2-3 closed throttle decelerations from >55mph down to 30mph. The P1000 can be set if the vehicle loses all power e.g. flat battery.

[Chopdogs]

I have a cheap OBD reader. There are no other codes.

The P0315 code cannot be reset by the reader - at least it resets then lights up again when the car is next started. I believe that it needs a relearn procedure to be fully reset.

The MIL has not cleared after several drive cycles.

I tried the coast down procedure at the weekend but no luck. Time for a dealer/specialist visit I think.

[Chopdogs]

I can confirm that the coast down procedure works.

I undertook the following (after advice from the good people at Bamford Rose - thank you!). I may have overdone it, but it worked for me.

Find a long straight road with no other cars (early Sunday morning worked for me)
Switch off all electrical inputs - climate contrail, lights, Bluetooth.
Switch off and restart the car
Delete the error code using an OBD2 tool
Put into D or accelerate up to top gear if in a manual
Get to 70 and stay there for a minute or two
Foot off the accelerator and allow the car to drop to 30mph
Do not use the brake
Use minimal steering inputs (hence the straight road)
I repeated this again (steering but not braking in between) but I’m not sure you have to
I then came to a halt (using the brakes) and left in D with foot on the brake for a couple of minutes
I turned off the engine, removed the key and left for a couple of minutes
On restart, there was no MIL.

Hope this helps someone along the line.


J

[Jon39]

Glad that you solved your problem, but what a palaver.
Has the world gone mad?

[Phil57DBS]

Hello
After discharge battery i have P1000 + P0315
i made this procedure and i still have these 2 errors !!!
What now please ?
Thanks

Edited by Phil57DBS on Tuesday 7th January 15:35

[Chopdogs]

P1000 code should clear by just driving the car. It seems to be a code saying that the on board diagnostic cycle hasn’t completed. It should clear by itself.

For the P0315 code, follow the instructions above and it will clear. All electrics off and a long straight road are required.....

[EVR]

As Chop said, P1000 is just OBD Systems Readiness Test Not Complete; as far as I understand this, it's when you turn on the car and then turn it off without turning on the engine (hence the tests have not been finished). Exactly what you do when you connect and OBD reader. So this one is no worries.

As for the other one I can't help unfortunately.