Battery Drain - Fan keeps running and running... Not FSR

rickead2000 · Apr 24, 2015

Hi

I have a 2006 RR L322. I have replaced the battery and fitted a new FSR (2 of them). When the engine is turned off the vents close down but there is a fan still running. It carries on running until the battery is flat -- literally to the point where the key fob won't even unlock the vehicle. I do not set the vehicle alarm (double click of the "lock" button) as I read that can cause battery drain.

Has anyone else experienced this problem and can point me in the right direction? It would be very unlikely that 2 FSR's have both been faulty but I am thinking it must be some relay somewhere.... maybe.

Thanks in advance!!

dolphinboy · Apr 28, 2015

Saint.V8 · Apr 28, 2015

rickead2000 said:
Hi

I have a 2006 RR L322. I have replaced the battery and fitted a new FSR (2 of them). When the engine is turned off the vents close down but there is a fan still running. It carries on running until the battery is flat -- literally to the point where the key fob won't even unlock the vehicle. I do not set the vehicle alarm (double click of the "lock" button) as I read that can cause battery drain.

Has anyone else experienced this problem and can point me in the right direction? It would be very unlikely that 2 FSR's have both been faulty but I am thinking it must be some relay somewhere.... maybe.

Thanks in advance!!

The HEVAC Panel fan can run on after ignition off, but should stop after a few minutes or so....are you sure it is the HEVAC causing the drain? pull the fuse(s) to it and see if it continues...if it does, it is not the HEVAC.

Another common drain is the headlamp wipers not parking correctly.

2.0_hippo · Apr 28, 2015

2006 so no headlight wipers to worry about

Where are you hearing this fan running ? From behind the dash or under the bonnet ?

rickead2000 · Apr 28, 2015

Thanks Saint.V8 -- I'm pretty sure it's the cabin fan as it's loud from within the dash but it sounds like when you take the key out it shuts the vents but the fan keeps running as no air comes out but it's pretty loud.

If I remove the end 40A fuse in the glove box fuse box, this causes the fan to stop and stops the battery drain.

Also I left the car with an almost flat battery over night and this morning I have found the passenger side pillar air-bag has deployed. Could this be relevant?

Saint.V8 · Apr 28, 2015

Hmm....airbags dont just deploy and a low battery shouldnt cause this.....maybe you have a wiring short somewhere under the dash that has shorted to the airbag causing it to go!

Datatek · Apr 28, 2015

Saint.V8 said:
Hmm....airbags dont just deploy and a low battery shouldnt cause this.....maybe you have a wiring short somewhere under the dash that has shorted to the airbag causing it to go!

As above, except a short should also not cause the airbag to deploy, the ECU can detect a short on the airbag line and disable it.
I can only think that low battery voltage has caused the SRS ECU to lose it's marbles.

Saint.V8 · Apr 28, 2015

Datatek said:
As above, except a short should also not cause the airbag to deploy, the ECU can detect a short on the airbag line and disable it.
I can only think that low battery voltage has caused the SRS ECU to lose it's marbles.

Possible, but I thought the SRS circuit/ECU had a series of capacitors in the system to power the system for a predetermined time and allow the system to discharge and shutdown correctly...

Low voltage from the battery would trigger the capacitors to discharge the system and shut the ECU down.....else there is a fundamental issue with dangerous and uncommanded airbag deployment which needs to be addressed by the manufacturers.

rickead2000 · Apr 29, 2015

I'm pretty convinced the issue is something to do with the battery constantly being flat due to the constantly running fan. There were no problems before this started.

Do you have any ideas for me to get stuck into at the weekend? Is there a particular relay I should be looking for or wiring harness etc?

Thanks again.

wil2813 · Apr 29, 2015

2.0_hippo said:
2006 so no headlight wipers to worry about

Where are you hearing this fan running ? From behind the dash or under the bonnet ?

ellis didn't you have a prob with water/wet srs ecu under console once ?

Battery Drain - Fan keeps running and running... Not FSR

rickead2000

Member

dolphinboy

Active Member

Saint.V8

Dyed-in-the-wool 100% RR Junkie

2.0_hippo

Well-Known Member

rickead2000

Member

Saint.V8

Dyed-in-the-wool 100% RR Junkie

Datatek

Well-Known Member

Saint.V8

Dyed-in-the-wool 100% RR Junkie

rickead2000

Member

wil2813

Well-Known Member

Similar threads