I managed to get it working via the IID tool, but only with the engine on. Some warm fumes out of the small exhaust, no smoke.
I have set the timed climate to come on in the mornings but no action yet.maybe not cold enough. Was 7 degrees today so maybe it needs to be 5 or below. Shouldn’t the fan come on anyway at any temperature?
I am sure it will be cold enough soon.

Hi Neilrrs,
If you have set the timed climate then it does not use the temp parameters to decide if it fires or not, it should come on as the TC has given the start command.

The temp/fuel level/ battery is for when you start the car and it decides it could do with some help to warm up!

Only way some peeps know it’s working if they don’t have TC or a remote is when they get the white smoke from the n/s/f corner and it’s not supposed to do it😁 just some do if not fired for a while.

I have not used an iid but connected mine via laptop and Discosticks remote and engine off you could run all parts individually, fan, glow plug, fuel pump etc to test each part and then fire it up, understand iid can do the same
Suggest you may have an issue with the fbh or TC keep playing with the iid
Best of luck
👍 Porsche Cayenne 2022
gone Porsche Cayenne 2020
gone Corris Grey HSE Dynamic 2016
gone Ipanema HSE lux 2010
gone Rimini HSE 2005
!!

with an iid you can do a test run which takes a minute or two.

it also clears lockout codes

On timed climate (or remote climate if fitted) it DOES use the temperature to decide if the Fbh fires.

External temp needs to be below 15 degrees. (If above this, then the fans only will come on and direct to face vents)
Water temp needs to be below around 73 degrees (unconfirmed exact figure but around that ) (again, fans only will come on to face vents if abive this)
Fuel needs to be in and above where the light comes on! (Won’t fire up if fuel level low)
Battery level needs to be above approx 12.13 (seems to fail below that level) (won’t fire up if battery level low)

Connect battery charger and try the timed climate again, this system is very susceptible to batteries that are 3 or 4 years old. May find it starts the car ok, but just not quite enough power to register the right voltage to run the timed climate.

Riverblanche, your car is the older type, so the Fbh will run regardless of the temperature if you use a FBH controller. EDIT no it’s not... you sure the Fbh fires up all the time or just that the fans activate? Bodsys Brake Bible
Software Updates Contact me
RRS Timed Heat/Remote kits - Contact me
BAS Engine Re-maps/ EGR Blank EuIII and EuIV
Clock On The Dash/ SNOTM /3Flash / BT Update /Service Reset/Error Codes read\ Gearbox Reset
See it HERE

Hi. Bodsy,
On the 2005 we had a “Discosticks” controller and istr (regarding temp) it just fired when command given.
The 2010 (3.0) was the one that Swmbo moaned at me about being too warm!!! It had fired not just fans
But happy to be corrected with the higher temp if using Timed Climate 👍 it could have been below that so fired and made the very car Toasty for her

👍 Porsche Cayenne 2022
gone Porsche Cayenne 2020
gone Corris Grey HSE Dynamic 2016
gone Ipanema HSE lux 2010
gone Rimini HSE 2005
!!

my fbh runs even when dash temperature shows centre position ie up to temp...my fuel consumption as gone from 24/25 to 17/18 mpg ..can i pull a fuse that stops it working when not needed ie long trip so i can get some economy..i have read somwhere that poor thermostat performance can be culprit ..but surely if gauge says up to normal temp the fbh should click off...any help appreciated happy new year..

i see it says fuse 28 controls fbh will i be doing any damage by removing this fuse

the whole point of it, should be that it improves economy.

If it isn't, then the car is clearly not as designed. Yes it could be thermostat.

But yes, when its 0°C outside, the FBH can run for the whole journey (and gauge at mid point)


They do run a cool down cycle, so it many not like the fuse being pulled half way through operation on a regular basis. I think they have 2 heat modes from memory,

That’s right, there are two heating modes. 2.8kw and 5.0kw

If the ambient temp is below 9 Celsius and the ECT is below 75 Celsius, the heater will start if all parameters are fulfilled (i.e. fuel & battery) and use full heating power until ECT reaches 87 Celsius. The heater then drops to low heat mode until ECT reaches 90 C where it then cycles off. All this is providing ambient remains below 9 C. If it rises above 9 C then the heat operation is cancelled, the unit goes through a cool down cycle and switches off.

The above is the operation for a standard FBH installation, the operation may be different for cars fitted with timed climate

I thought they only fired up around 4/5°C

I’m quoting from the service manual, it says 9 C....

While the engine is running, if the ambient air temperature is less than 9 °C (48 °F) and the ECT is less than 75 °C (167 °F) the ATC module changes the status message from 'heater off' to 'supplemental heat'. The control module then changes the status message it sends the ATC module to 'supplemental heat' and starts the FFBH. The control module will not start the FFBH, or will discontinue operation, if any of the following occur:
The control module is in the error lockout mode (see Diagnostics, below).
A crash message is received from the restraints control module (RCM).
For additional information, refer to: Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS) (501-20B Supplemental Restraint System, Description and Operation).
A low fuel level message is received from the instrument cluster.
For additional information, refer to: Instrument Cluster (413-01 Instrument Cluster, Description and Operation).
The engine is not running, or stops running for approximately 4 seconds. The time delay is included for stall protection.
If the control module does not start the FFBH, or discontinues operation, the status message to the ATC module remains at, or changes to, 'heater off'. If the ambient air temperature increases to 9 °C (48 °F), or the ECT increases to 75 °C (167 °F), the ATC module cancels supplementary heating, by changing the status message to the control module back to 'heater off'. The control module then cancels FFBH operation and changes the status message to the ATC module to 'heater off'.
The FFBH is controlled at one of two heat output levels, 2.8 kW at part load combustion and 5 kW at full load combustion. The control module transmits the amount of fuel used by the FFBH to the instrument cluster, and the FFBH coolant temperature to the ATC module.

Hi,
Millsy our economy hardly changed during the colder months so if yours has dropped that much may be it suggests something else is wrong and not just the FBH doing is job, you should be happy its working
better to get the thermostat fixed IF it is that

It is surprising how quickly the engines can cool down when stopped or even driving steadily/slowly and the car decides it needs a bit of help from the FBH

 Porsche Cayenne 2022
gone Porsche Cayenne 2020
gone Corris Grey HSE Dynamic 2016
gone Ipanema HSE lux 2010
gone Rimini HSE 2005
!!

hello guys thanks for input..i cant remember where i read about thermostat ..it said that if thermostat was wide open would effect fbh ..i just didnt fancy changing it at this time of year ..but as you say your mpg didnt drop so badly i must have some problem..i have long trip monday to felixstowe must be three hundred miles round trip ill see if it improves with a run..ive only been local lately..i suppose its all about where the fbh takes its temperature control from..i though logically be on same route as temp gauge but im no sparky..my rrs is se so i dont have on dash diagnostics ..in retrospect its a mistake to not have i thought it was just sat nav i would not have..duhh If i remove fuse after cool down period will it be ok to do that..i could then test return mpg if it fails to clear..will pulling fuse reset fbh ..it may be all it needs just for your info i have no lights or warnings on my dash ..its a 2.7 diesel se 2006 vintage with 91k on clock runs great

Last edited by millsy123 on Wed Jan 03 2018 10:45pm. Edited 1 time in total

Don't think you are missing any HSE features.

YEAH PULL THE FUSE