kernowdragon
Well-Known Member
If you describe the symptoms and what you've tried already you might get some suggestions at a fix, many people have suffered from this....
kernowdragon
Well-Known Member
Has it always done it, or is this a new thing? Many of the faults people have experienced have been related to EFI causing the cars electronics to remain awake, rather than going into standby as they should. Is there a new transmitter of any kind nearby, cell tower, traffic or other telemetry point etc.?
I have had four battery's in three years, all premuim grade. The latest is only 4 months old and its a genuine part.
They have fitted an isolator switch to the the gubbins under the rear trim, that has'nt worked, but it does make the vehilce unstealable ! (mind u the flat battery does that too)
They have fitted an isolator switch to the the gubbins under the rear trim, that has'nt worked, but it does make the vehilce unstealable ! (mind u the flat battery does that too)
Datatek
Well-Known Member
Petrol or diesel and what capacity batteries have you fitted?
You need to see if the BECM is actually going to sleep.
Have you tried pressing the mode button? Apparantly this forces the BECM into sleep mode, I haven't tried it though.
Datatek
Well-Known Member
Get the alternator checked for leakage current.
As I say, I have had an isolator swithed fitted, as the garage was convinced this was the problem, I now flick a switch and it renders my fob useless, therefore I presume nothing else should wake it? that being said, the park light still glowed dimly, until I pressed the mode button as recommended by datatak..... I will check the alternator for leakage current, although I have ready been told by one "diagnostic engineer" that the drain is quite significant, he just never found the root of the problem....
Although I have disconnected the Blue wire completely, I can still use the Key fob, it may be worth seeing which wires they have isolated. With the blue wire unplugged, I can still open the doors etc , but it just means that you need to be closer to your car for it to work.....
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Datatek
Well-Known Member
Are you completely disconnecting the RF receiver not just aerial? Could be the RF receiver itself is duff. The other thing that will cause battery drain is the engine compartment fuse box. Check for burning smells and look at relays 6 & 7.
v8hotrodboy
Active Member
Pretty sure that just turns the little red light off, but the becm stays awake, you can hear a faint electical noise if you listen very carfully.
Have you tried leaving the car unlocked? My becm stays awake if you lock it but sleeps if you dont!!
discomalc
New Member
I found this useful in trying to figure out my battery drain problem.
BECM Sleep Test
This test will determine if the BECM goes to sleep properly or it will stay awake.
1. Sit in the vehicle in the driver seat with all the doors closed.
2. Wait until the interior light switches off.
3. Switch on the ignition.
4. Switch off the ignition.
5. Open the driver door and leave the door open for the reminder of the test.
6. Switch off the interior lights by pressing the button for 4 seconds. On the message centre you can observer the message "Lights off".
7. The message centre displays "Ignition key in" for approximately 2 minutes.
8. If the display goes blank after the two minutes, then the BECM is gone to sleep, if the display is still on, then the BECM did not go to sleep.
i found my becm was sleeping correctly but continued to watch the message display and red gearbox light and found that something was waking it up again very shrtly after it was sleeping. traced it to a wireless weather station the missus had moved into the front room .
BECM Sleep Test
This test will determine if the BECM goes to sleep properly or it will stay awake.
1. Sit in the vehicle in the driver seat with all the doors closed.
2. Wait until the interior light switches off.
3. Switch on the ignition.
4. Switch off the ignition.
5. Open the driver door and leave the door open for the reminder of the test.
6. Switch off the interior lights by pressing the button for 4 seconds. On the message centre you can observer the message "Lights off".
7. The message centre displays "Ignition key in" for approximately 2 minutes.
8. If the display goes blank after the two minutes, then the BECM is gone to sleep, if the display is still on, then the BECM did not go to sleep.
i found my becm was sleeping correctly but continued to watch the message display and red gearbox light and found that something was waking it up again very shrtly after it was sleeping. traced it to a wireless weather station the missus had moved into the front room .
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