968 battery drain problem

Richy_S · **Posted:** Tue Nov 17, 2009 8:46 pm

Hi Guys

Trying to diagnose a battery drain problem on my 968 - i assume the following will be the same on an S2 etc

Measuring the current with every thing swiched off I am finding that it is going up and down with a clicking noise from within the car.
Tried disconnecting all fuses but it is still there, then tried disconnecting the alarm - again still there.

The clicking seems to be coming from the near side rear quarter - I am guessing that as it is something that is powered with all the fuses removed it might be the immobiliser.

Its a factory fitted unit - can anyone confirm its location is behind the ns rear quarter I.e alongside the rear seats before I pull it all apart?

Rich

hotblack944 · **Posted:** Tue Nov 17, 2009 9:15 pm

Hi Rich,

I always thought the clicking from the near side rear in my S2 was from the ultrasonic sensor on the factory alarm - it clicks when you move about and stops when you stay still. If yours is clicking all the time, maybe your ultrasonics are goosed?

Richy_S · **Posted:** Tue Nov 17, 2009 9:18 pm

Theres a aseparate control box for them and I have disconnected them.

Now beginning to think the immobiliser is under the passenger seat.

Rich

zola1 · **Posted:** Tue Nov 17, 2009 9:47 pm

What amount of drain have you got? are we talking mA's or Amps

Derrick

Richy_S · **Posted:** Tue Nov 17, 2009 9:54 pm

zola1 wrote:

What amount of drain have you got? are we talking mA's or Amps

Derrick

Approx 300mA reducing to 150mA when hearing the click - I guess the difference is the coil of a relay.

Started of with 500mA+ - old favourite, glovebox light.

Rich

zola1 · **Posted:** Wed Nov 18, 2009 9:25 pm

yes i agree, 80 ohm relay windings = approx 100mA draw,what is the OEM immobiliser on a 968 q1.What do you use to disarm the immo ? is it a manual type receptacle ? or is it passive i.e it has an Ariel loop around the ign barrel so the user has a transponder (either in the key or a dongle hanging form the key.

i don't have any 968 circuits to hand just coming at it trying to get my head around it...,as normally any immo would not have such a high quiescent as the only circuit to stay "high" would be the LED telltale 10-20mA max.

have you located the immo ecu ..you mentioned under the pass seat ?

ExAudiSi · **Posted:** Wed Nov 18, 2009 9:37 pm

Usually the factory fitted stereo amplifiers reside under the front seats, one on each side.

Richy_S · **Posted:** Wed Nov 18, 2009 10:13 pm

Yep found the immobiliser under the passenger seat. Its a steel box that has no way of opening up simply.

Sitting in the car with all off I hear the occasional click from a relay within the immobiliser - when this clicks the current drain from the battery decreases. There is a local gnd contact which I need to check but other than that I think it will be a call to Hamilton and Palmer.

Rich

zola1 · **Posted:** Mon Nov 23, 2009 12:17 pm

Richy_S wrote:

Yep found the immobiliser under the passenger seat. Its a steel box that has no way of opening up simply.

Sitting in the car with all off I hear the occasional click from a relay within the immobiliser - when this clicks the current drain from the battery decreases. There is a local gnd contact which I need to check but other than that I think it will be a call to Hamilton and Palmer.

Rich

Did you have a luck getting info on the immo from them ?........are they all black wires for the unit etc ?

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968 battery drain problem

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