Flat Battery - yet another electrical issue...GOD HATES ME

[Steamyrotter]

The webadto is there to improve efficiency.
It enables the coolant and hence engine get up to temperature quicker and then run more efficiently.

You don't need it, and keeping unplugged will not make any difference, other than taking longer to get up to temp.

There is a fan in there which can appear t sound like its accelerating to warp 9.9!!
You can interrogate them with appropriate lead and software.
I believe there is a link to that somewhere on here..

[Horizon]

Sounds like a dicky PCB within the webasco. The webasco normally needs an external trigger ( pin 1 ) to active it. There is permanent power to the unit which will enter the PCB , when an external trigger is sent,IE timer or low ambient temperature signal the board will activate a relay to power up the burner/ pump etc.
A bit of dampness or corrosion on the board could cause the board to act up
I would leave it disconnected. Mine never fired up properly and I didn't bother getting it fixed.
Temperatures havnt been very low this year either.

[X5-D-Sport]

UPDATE......
No start this morning...
Safe to rule out the Webasto now, as it was disconnected all night...
Down to 8 volts this morning.

The car definite went to sleep mode - re LED at the "P" position went out after 10 mins or so...
Boot cavity is dry & dusty, so no soggy modules...
Will test the current draw with the vehicle idle.... & use a clamp meter to not disturb whats going on...

Im going to get it jump started soon, & wiz down to the motor store and test the battery properly & see if its faulty on their tester... but I do think the battery is OK - new 6 months ago & 1,000 Crank Amps... its a monster...

I'm pretty sure there is a big power bleed going on some where....
Any clues where to start looking ?

[Steamyrotter]

oh poo

not good 

Have you changed the hedgehog resistor??
Have read that that can cause unusual current drain.

Also seem to remember on another forum someone suffered from a suspect ignition switch block.

[X5-D-Sport]

What is the hedgehog resistor ?
Is that the gizmo that controls the interior blower fan speed ??

The initial issue could possibly be as follows...
the vehicle went nowhere for 2 weeks. ..except  odd 1/2 mile trips into town... lights on at tickover in traffic for 30 mins a time...
then unused for a whole week...

just checked to SLEEP current draw which has settled to under half an Amp at 0.44 amps / 440mA which sounds about right to keep the memory alive, the alarm & an LED on the mirror too..

what is the official SLEEP draw current for a diesel X5 ??

[X5Sport]

I can't imagine leaving it disconnected will be an issue.  All it's for is the speed up getting the car warmed up as said.

Current clamp certainly the way to go.  If you've got the INPA running you can check for errors to see if there is anything recorded.  If not then it's the slow, frustrating process of pulling fuses until the power draw disappears.

I know you say it's a new battery, but dropping to 8V sounds suspiciously like 2 cells are iffy and have high resistance shorts in the cell matrix.  What's the production date on it?

You can always check if it is a draw by putting a voltmeter on and then disconnecting it.  If the draw goes then the volts will bounce back - if I remember my battery theory correctly.

[R515]

According to DIS, an X5 shouldn't be drawing any more than 40mA after 16mins, if yours is 440mA, that's a major draw and way above spec!

[X5-D-Sport]

Noted... doesn't sound much... too little actually me thinks.

Not sure how they can quote 40mA... that's 0.04 Amps....
The flashing LED in the mirror will draw that alone, let alone the ultra-Sonics in the alarm.
The sensing processor alone will draw 60mA, without any of the support electronics.. AND the receiver for the remote locking will draw an additional 150mA as separate devices, let alone being fed from a computer governor in sleep mode...
So, my guess is that 450mA is probably about right.

[stevox5]

The draw should be approx 0.04 A after 16 mins or 32 mins depending spec of the car.

Likely suspects are ..
Heater output stage resistor
Auxiliary engine pusher fan .
Traffic master control unit (if fitted)
Faulty battery in a tracker system trying to charge itself - this has caught me a few times..

If none of the above you may have to start pulling fuses one by one to find the circuit with the draw.

Good luck

[X5-D-Sport]

Okie, sounds interesting...

Heater output stage resistor                                              maybe ????
Auxiliary engine pusher fan .                                            (fan is dead & never worked)
Traffic master control unit (if fitted)                                  (not fitted)
Faulty battery in a tracker system trying to charge itself -  (doesn't have a tracker)

Thus leaving the heater output stage resistor.... is this the item referred to as the "Hedgehog" for the interior blower fan  ??
This fan is working perfectly as far as blowing & operating goes.

Wondering if I can get access to it, so I can let it dangle & see if it is warm several hours after the vehicle has been stopped...
What says you Stevo ?

[R515]

As I said in my earlier reply, now mine is sorted, it only draws 20mA when in sleep mode!. You're going to have to pull fuses until the circuit responsible for the excessive draw is identified.

Good luck,

Mark

[Steve p]

hi , i had the same problem with my 06 x5 i tried everything battery,hedgehog resister etc , turned out to be a faulty starter motor renewed starter motor I've never had a flat battery since. hope this might help
regards ste

[stevox5]

I would certainly disconnect it first mate only one connector on it and easily accessible behind bottom of heater box by the fire wall on the drivers side .
Remove the panel under the pedals and the trim running along the bottom of the center console and it's right at the back pushed into the heater box.

Have a look on here or x outpost and I'm sure there is a guide for it .

[X5-D-Sport]

Hi Stevo,
*** I'm presuming this unit under the drivers panel is the hedgehog ??

I can jerry-rig the connections with an Amp Meter in place... maybe this is there the extra 420 mAmps is going...

The will check the starter power supply & see if thats gobbling power when idle also...

thanks guys, update tomorrow.

whats the technical name for the Hedgehog resistor thingy ??

[Steve p]

fully charge the battery then id disconnect the starter motor and leave for a few days  then reconnect the starter  ,thats what i did battery still had a full charge and car started fine,the next day battery would be flat with it connected.new starter cured the problem and the car turned over a lot  faster.
regards ste