Didn't have time for tuning lately, univesity is taking most of my time...
Sadly now I need help :!:
Preheating on my 406 is not working anymore :wtf:
In fact, with these temperatures next to zero, the engine struggles to start and is very unstable after it starts..
I leave it idle for a few minutes until it stops oscillating between 800rpm and 1000rpm :crazy:
After it warms up a little bit everything is back normal.. yay!
I took a look at Peugeot Service Box and it says 406s have 2 types of preheating plugs: OBD-compliant and non-OBD.
I have non OBD so I can't diagnose what's wrong.. all 4 plugs have just a black wire connected to them...

From the Technical Document on EDC15C2 I learned that preheating is driven by coolant temp. So I first thought: maybe that sensor is broken, but it isn't. Coolant temp displaying correctly in PP2000.

My question is:
Does anyone know where it is OR how can I find the map that controls preheating?

Last but not least:
What Voltage is given to the glow plugs?
I'd like to give them the same voltage in the garage before starting the engine in the morning

Are you running on your map file where you have changed the axis? If so this will be your problem I think. To confirm, load your org back in and see if your preheating comes back ;-)

Had this issue on mine and only noticed it when I replaced my mod file that had axis changes back to an org and all my cold start problems went away!

Voltage will be nominal battery voltage, so around 12.5 volts.

Ok
I just put original bin on.
Engine is warm right now so I have to wait to see if it works..
Thanks a lot!

Alex, I think you search in wrong place. Before look at sw you need test hw. Easiest way to test glow plugs - connect it to battery cross bulb. If bulb not light - glow plug is fault. Next step - glow plug relay. And other step - glow plug fuse, but this very seldom reason.

The reason I suggested to check the SW first was that I know Alex is running a modded file which I think (I maybe wrong) has the IQ axis modified. When I did this on mine, the preheating didnt seem to be functioning correctly. Swapped back to ORG file and all was ok.

Of course if it doesnt work, then yes a hardware check is certainly the next step! ;)

Thanks guys :thumbup:
In my case Ross is right, SW was the problem.
Yesterday I put original sw on, and this morning I put a voltmeter on the glow plugs and when i turned the key voltmeter showed 12V and after a few seconds I even heard the relay switching off and voltmeter said 0V

Now...
How can we find preheating map / maps ?
we know it's coolant based, it shoud be unidimensional, and values in the map should be seconds..

ross2482 wrote:IQ axis modified. When I did this on mine, the preheating didnt seem to be functioning correctly. Swapped back to ORG file and all was ok.

It makes me wonder... what does IQ axis have to do with preheating?

AFAIK
preheating = ƒ(coolant temp)
post-heating = ƒ(coolant temp , rpm)

Ah ha, glad it worked.

Adjusting the IQ axis just isnt worth the bother on these, I had all sorts of issues on mine with the pre-injection values being dangerously high with altered IQ axis. We obviously havent got the experience yet to know which maps rely on the IQ axis to go about just adjusting them!

Post heating also has an IQ input, AFAIK once IQ goes above a certain value, post-heat is disabled. It is enabled again once IQ drops back under a certain threshold.

I guess I'll have to redo my tune without touching IQ axis at the beginning of map area :(
But I'm glad to say that I've been running this mod (step 13 from 406 2.0 HDi RHZ project thread) since August 2012 !! 8-)
Didn't have any problems till winter came and preheating didn't work...
Now exams session is coming again :roll: just like that september session that stopped me from tuning...
I really hope I get to redo this tune and get to step 14 realy soon :)

Question still open:
How can we find pre/post-heating maps?

maybe ecuedit gives us a hint :D