HEVAC fault logging.... Nanocom....

Hi, I am getting the book symbol up on the HEVAC intermittently, it does seem to clear itself rather than needing to be reset.

I have hooked up the Nanocom but it is reporting no logged faults. However I know there are some issues with Nanocom talking to HEVAC which will hopefully be resolved with the next version of the firmware.

So - does anybody know: Should the HEVAC store all its fault codes, even if the fault condition has gone?? The Nanocom documentation suggests the answer is yes, but I was wondering if anybody can confirm this?

I am sure I have an intermittent problem so being able to see stored fault codes would be very helpful.....

Also - can I hook the Nanocom up before setting off on a drive and observe input values (or even better, log them on SD card) whilst driving along, or does the HEVAC ecu kill comms with the Nanocom above a certain speed (like the ABS ECU does...)?


Cheers,

Jerry

Go to the Nanocom site and ask the question there. I believe the problem is with clearing faults not in logging them.

The Nanocom at the moment doesn't "see" the faults or clear them the fix is due this week.

yes you can drive around with the Novacom displaying inputs , you can set the unit to catch lowest or highest figures using the graph buttons.

No idea about writing to sd card haven't tried.

When I fixed my Hevac blend motors and core temp sensor the book symbol went off but the codes were still stored by the HEVAC until cleared with the BBS FCR.

Does sound like I need to wait for the update then - and that is what nanocom say too!

I did some investigating today - drove with the Nanocom connected and am getting crazy readings for both external air temp and heater matrix temp - sometimes the matrix reading goes sensible - the ext temp stays crazy (something like 3500 deg). What is odd is that the ext temp display on the HEVAC is fine. Surely they use the same sensor? Sadly, this makes me think it is actually the Nanocom at fault....not the sensors/HEVAC. Anybody any views on this??

It is bad when one has a diagnostic tool that is less reliable than the thing you are diagnosing (which is saying something with a P38! ;-) ), however I am wondering if this is the case at least for the HEVAC. Disappointing if it is, but hopefully the update will sort it out.

Cheers

Jerry

Those Valeo HEVAC panels love logging faults - Testbook would show them.The only time they wouldnt log a fault is if the panel itself is faulty,which is not unknown.I have even had a faulty brand new one out of the boxfrom LR.Which is why I have a 'known good' one on the shelf for testing.

You could always use a multimeter and measure the resistance of the sensors. I recently bought a new heater core temperature sensor and at room temp it measured 40k Ohms.

jerrytlr said:

Does sound like I need to wait for the update then - and that is what nanocom say too!

I did some investigating today - drove with the Nanocom connected and am getting crazy readings for both external air temp and heater matrix temp - sometimes the matrix reading goes sensible - the ext temp stays crazy (something like 3500 deg). What is odd is that the ext temp display on the HEVAC is fine. Surely they use the same sensor? Sadly, this makes me think it is actually the Nanocom at fault....not the sensors/HEVAC. Anybody any views on this??

It is bad when one has a diagnostic tool that is less reliable than the thing you are diagnosing (which is saying something with a P38! ;-) ), however I am wondering if this is the case at least for the HEVAC. Disappointing if it is, but hopefully the update will sort it out.

Cheers

Jerry

Click to expand...

Its early days for the Nanocom dont loose faith in it yet.

I'm a long way from losing faith! All of the other systems seems to work perfectly as far as I can tell, and the fact you can do everything with no laptop, and even when on the move, is amazing. I have no regrets about my purchase.

It is just a shame that the initial reason for purchase - to try and figure out what is going on with the HEVAC - has not worked out as well as I had hoped.

Cheers,

Jerry

The MSV can have difficulty in communicating with the Hevac if the Becm is unlocked.The Nanocom may have the same issue.

You are correct
In the blurb about the Nanocom it mentions difficulty if the Becm is unlocked, talks about disconnecting a plug..

Just Updated my Nanocom and it works on the HEVAC faults now.... Also added a snazy instrument display for when driving with it connected. E.G shows live battery voltage

Me too, and it is reading/clearing the faults fine now - but unfortunately it still seems to struggle a bit talking to the HEVAC ECU, anybody else finding this? Takes me several attempts to get it to work...

The new instrument display is good.... as is the 180 rotation, with mine being LHD ;-)



Cheers,

Jerry

yes .. but it gets there in the end.....