P38A For what valid reason would you disconnect the BBSU?

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DanClarke

DanClarke

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Daft question maybe, but I was wondering why the new Rangie doesn't do the double "Whoop-Whoop" for indicating mislock when it has been set to do so. Pulled the battery cover off and it allowed me to see the BBSU and "surprise-surprise" it was not connected! The Brown multi-plug was lying to one side.
I gave the pins on the back of the BBSU a scrub with contact cleaner and reconnected the connector.
The settings say to use the BBSU for mislock notification, but not a peep.

Could it have been disconnected because it was draining the main battery? Is this likely?
Because it was silent I have ordered a replacement BBSU anyway. But its disconnection and the reason for that event is unknown.
 
BBSU = Backup break-in Sounding Device?

If it is the buzzer thing then the rechargeable batteries inside tend to die and then it starts going off for no reason at all. I even heard tales of them bursting into flames on the shelf for the old Vauxhall Omega. Lithium batteries are doped with other metals and depending what goes into the mix you can end up with some quite reactive mixes. Add some internal resistance (=heat generation) and you can end up with a runaway exothermic reaction quite quickly - as Boeing discovered.
 
Grrrrrr said:
BBSU = Backup break-in Sounding Device?

If it is the buzzer thing then the rechargeable batteries inside tend to die and then it starts going off for no reason at all. I even heard tales of them bursting into flames on the shelf for the old Vauxhall Omega. Lithium batteries are doped with other metals and depending what goes into the mix you can end up with some quite reactive mixes. Add some internal resistance (=heat generation) and you can end up with a runaway exothermic reaction quite quickly - as Boeing discovered.
Click to expand...
Hi Grrrrr,
I think BBSU is "Battery-Backed-Siren-Unit" and it is the high Db-Level alarm sounder that goes off on a break-in. I believe it takes a charge from the vehicle to keep itself topped-up and if thieves manage to disconnect the battery (or drill a hole through it from underneath to drain the battery electrolyte) the BBSU is meant to have sufficient internal charge to run for 4.5 mins on its own.
I never had a problem with the BBSU on the last Rangie and its my preferred alarm/mislock sounder. I was trying to work out why someone would pull its plug so to speak.
I do hope it doesn't burst into flames on my drive.
 
Last edited:
wammers said:
It's a BBUS by the way. ;):D It will sound for up to 40 minutes if the battery is disconnected incorrectly.
Click to expand...
Yes, you are right! my mistake. 40 Mins at a time!!!! no wonder they disconnected it.
I shall play tomorrow. My nanocom guide says I should be able to set it to "ON" and then "Off"via the dog-nastys.
If it fails then the replacement unit can be tried in a few days time when it arrives. Thanks Wammers :)
 
kds said:
Mines disconnected because it decided to go off willy nilly while I was driving down the road.
Click to expand...

Probably the internal rechargeable battery failing so thought someone was tampering. I don't have one on mine so never seen it but suspect it might have the old R/C car type nickel cadnium batteries inside. If so you can probably get replacements from Maplin or similar.
 
wammers said:
It's a BBUS by the way. ;):D It will sound for up to 40 minutes if the battery is disconnected incorrectly.
Click to expand...

But when you consider the life of the nicad battery fitted is around three years it's doubtful that any battery backed-up sounder will still have its original function, easy identified of course buy not having to follow the on-off routine with the ignition key before disconnecting the vehicle battery.
 
OK now I am somewhat confused.
Yesterday, despite all my efforts I could NOT get the BBUS to sound with the BeCM settings set to confirm Alarm Enabled with Sounder (not flash internal lights) and with choice of sounder set to BBUS and pulsed and not Klaxon.
The BBUS was left connected all night (just in case it needed a decent bit of time to get charged up from the main battery.
Tried it again today...still no joy. Checked the setting were all OK and wrote all settings to BeCM and got the "all written OK" confirmation message.
Tried the section of the Nanocom that allows you to purposely trigger thing;s and when I told it to trigger the Alarm I got the cars horn on continuously and not the BBUS even though the settings (just checked and written to memory and confirmed as "OK". Thought to myself, this is Bonkers.
Disconnected the Nanocom, turned the ignition to position 2 and then off again and removed the key. Pressed the close button on the fob with the drivers door open and the bloody thing did the double chirrup on the BBUs that I have been striving for all this while.

All I can imagine (although I would have thought it unlikely) is that even if you can write whatever new settings you like to the BeCM via the Nanocom they don't come into force until the next start-up/shut-down of the BeCM. I am really puzzled.
I'm not a slowpoke at fault-finding or reading instructions, I spent 20 years as an IBM customer engineer and a further 22 as a technical solution designer. But this car defies all normal logic it seems. Of course it does... silly me...its a Land Rover.
 
Last edited:
DanClarke said:
OK now I am somewhat confused.
Yesterday, despite all my efforts I could NOT get the BBUS to sound with the BeCM settings set to confirm Alarm Enabled with Sounder (not flash internal lights) and with choice of sounder set to BBUS and pulsed and not Klaxon.
The BBUS was left connected all night (just in case it needed a decent bit of time to get charged up from the main battery.
Tried it again today...still no joy. Checked the setting were all OK and wrote all settings to BeCM and got the "all written OK" confirmation message.
Tried the section of the Nanocom that allows you to purposely trigger thing;s and when I told it to trigger the Alarm I got the cars horn on continuously and not the BBUS even though the settings (just checked and written to memory and confirmed as "OK". Thought to myself, this is Bonkers.
Disconnected the Nanocom, turned the ignition to position 2 and then off again and removed the key. Pressed the close button on the fob with the drivers door open and the bloody thing did the double chirrup on the BBUs that I have been striving for all this while.

All I can imagine (although I would have thought it unlikely) is that even if you can write whatever new settings you like to the BeCM via the Nanocom they don't come into force until the next start-up/shut-down of the BeCM. I am really puzzled.
I'm not a slowpoke at fault-finding or reading instructions, I spent 20 years as an IBM customer engineer and a further 22 as a technical solution designer. But this car defies all normal logic it seems. Of course it does... silly me...its a Land Rover.
Click to expand...

The chirp locking with door open is a mislock signal. Did you do changes to BECM settings in diagnostic mode?
 
wammers said:
The chirp locking with door open is a mislock signal. Did you do changes to BECM settings in diagnostic mode?
Click to expand...
Yes, I did the changes in Diag Mode (no key in) and with "Diagnostic Mode" displayed on the console. I thought that is what you had said to do?
Did I misunderstand you?
It was the chirrup on mislock, I was trying to set up. Rather than Internal lights flashing. At least I have what I wanted now. I'm just as confused as a confused thing because it wouldn;t do it yesterday or earlier today. :)
 
DanClarke said:
Yes, I did the changes in Diag Mode (no key in) and with "Diagnostic Mode" displayed on the console. I thought that is what you had said to do?
Did I misunderstand you?
It was the chirrup on mislock, I was trying to set up. Rather than Internal lights flashing. At least I have what I wanted now. I'm just as confused as a confused thing because it wouldn;t do it yesterday or earlier today. :)
Click to expand...

Good you got it sorted. BBUS battery flat as a pancake and needed time to charge more than likely. ;)
 
wammers said:
Good you got it sorted. BBUS battery flat as a pancake and needed time to charge more than likely. ;)
Click to expand...
I hope it was that. Shame I jumped the gun and got a spare "working" BBUS in the post today. LOL, there's £15 I wont see again.
Only got the Cruise Control to get fixed now and it will be 100%.
 
I tried that, it was rotten and all perished and those bits I replaced.... but...... It then started working at least.....but it kept accelerating in random jumps & spurts, beyond the set speed. Quite interesting in a scary kind of way on a major road.
Dealer tried to fix it but got nowhere; and now it is totally nadgered. ATM I cannot get any comms to the ECU on the Nanocom, although I do hear the relay click when the set button is pressed.
Its not urgent, just a "nice-to-have. :)
 
DanClarke said:
I tried that, it was rotten and all perished and those bits I replaced.... but...... It then started working at least.....but it kept accelerating in random jumps & spurts, beyond the set speed. Quite interesting in a scary kind of way on a major road.
Dealer tried to fix it but got nowhere; and now it is totally nadgered. ATM I cannot get any comms to the ECU on the Nanocom, although I do hear the relay click when the set button is pressed.
Its not urgent, just a "nice-to-have. :)
Click to expand...
Have you tested the vac pump? Pretty easy to check.
If the relay is clicking then it is trying to set so it's either not making any vacuum or said vacuum is leaking away somewhere. Could be bellows.
You can bridge the vac pump and see if it hold the bellows in.
Can't remember the wire colours but look it up on Google.
 
discool said:
But when you consider the life of the nicad battery fitted is around three years it's doubtful that any battery backed-up sounder will still have its original function, easy identified of course buy not having to follow the on-off routine with the ignition key before disconnecting the vehicle battery.
Click to expand...

It is sensible to do so before disconnecting battery whether a BBUS is fitted or not.
 
Thanks all (as always) for the pointers, will take a look.
Being so ruddy short getting at stuff over the wing of the car is always a challenge.
"So why have such a big car Dan?" ..... Perhaps I am compensating for something Ha! Ha!
 
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