Thread: Battery drain - gear selector lights

When the vehicle is left and all timers have timed out the BECM goes into "sleep" mode which reduces current draw to about 40 mA with the alarm armed. When an input is sensed (eg unlocking the vehicle), it returns to activation mode with a current draw of about 1 amp. This is the cause of some of the battery drain problems some owners have experienced when parked in areas of high radio interference -- the BECM keeps getting "woken up" by the alarm system's RF receiver. If this happened constantly the battery could easily be dead within 24 hours.


To test.

Park the vehicle in a dark garage. Put the gear lever in park.
Lock the vehicle. Look at the gear position indicator lights. Once the interior lights have faded and your eyes have adjusted to the dark the neutral position indicator light will glow red faintly. After a while the light will go out and the BECM will go to sleep. If it does go out check the garage every few hours to see ft the light stays out.

Blindin, has anything changed where you park?...for example a new garage auto door in the street,alarm etc.... I Had this happen to me whereby parking at my home makes my battery go flat but if I park anywhere else it's all good..... I Pulled the lead from my RF receiver and haven't had a problem for the past 2 years.....only down side is to use my remote I have to place it close to the rear d/side glass.....I know there is an update receiver, not cheap, I just haven't got around to sourcing one....may be worth a try to unplug and see if the battery goes flat.

Hi, this isn't any thing to do with the alarm.
The issue is that the light on the gear selector ( the little red lights to tell you what gear is selected ) was staying on when the ignition was turned off. I haven't checked where the power comes from, but with the ignition off it should not have been lit up regardless of when the door was open / alarm etc...
I had originally thought that so didn't pay any attention to it. But today, I can open the door and close it with no light. As soon as the ignition is turned on, the light comes on, as soon as ignition is turned off, the light goes out. And does not come on again until the ignition is switched back on.
It must of had power from some where the other day to make it stay on.

Mine was coming on faintly as the RF was waking the becm , ....just thought it may help.

Blindin, what he was referring to is a common P38 battery drain issue whereby rf frequencies cause the BECM to stay awake with the vehicle locked (whereby you see the light on the tranny selector stay on).

Some don't seem to have this issue, others do.

Cheers
Keithy

Ah ok. I do know about the alarm keep the becm awake. Is that a symptom of it then?
I'm just about to have a look through rave to see if I can find any thing.
I noticed it at 2 different places on tuesday. 1 of them at home where it is always parked.
This morning ( hasn't been driven since tuesday ) the battery was completly flat. My key fob does not work, so it will only ever be looked with the key.
As mentioned before, the selector light stayed on faintly on tuesday, but I didn't take much notice of it. Today it is going off.

So are you saying that if the becm is picking up any type of frequency, the selector light will come on?
Is there any thing else which would allow the selector light to come on with no key in the ignition?

I have had a flat battery before on a couple of occasions, I have been working on the stereo, and thought I had done some thing wrong, and then installed another cable from the alternator as that was not putting much voltage to the battery. Now I am thinking its the same problem.

I don't think rave will help you as much as rangerovernet will....simply search for RF receiver, there are many situations to read about.
If you are only using the key you should disconnect the rf receiver aerial and you may find it'll fix your problem. Keep in mind that the remote is the recommended way of entering your vehicle as using the key only could be a disaster if the lock fails, but that's aanother story.

[
To test.

Park the vehicle in a dark garage. Put the gear lever in park.
Lock the vehicle. Look at the gear position indicator lights. Once the interior lights have faded and your eyes have adjusted to the dark the neutral position indicator light will glow red faintly. After a while the light will go out and the BECM will go to sleep. If it does go out check the garage every few hours to see ft the light stays out.[/QUOTE]