Plip batteries

[Doggy]

For the last week or so, my car has sometimes been reluctant to lock via the remote control, but has always unlocked. Suspecting this might be the battery failing, or maybe some fluff in the switch, I looked out the spare key last night with the intention of trying it when the original next failed to work.

Checked the spare worked, then unlocked with the original. I started the engine and.... Bong! 'Warning Plip Battery Low', (which I've heard of but never seen before). I shall be investing in a CR2016 coin cell forthwith.

Question is, how does it know?

[Welly]

Prove it.

[gumby6371]

Presumably it must talk to the key when its sitting in the ignition barrel and have a set parameter for the strength of the return signal???

BTW home bargains do the batteries at a fraction of the cost of 'branded' ones, its the same for CMOS batteries in PC's and laptops they're ridiculous prices!

[steve_earwig]

I had this message on my D9 about 3 years ago and the plip still has the same battery in it Gumby's idea gets my vote, it's a set distance from the receiver so a good place to test it.

Meanwhile, the battery in the yoyo's plip (oh here we go again with Steve bleating on and on about how crap his Toyota is ad nausium) has definitely gone flat (or else the plip's died). It gave me due notice by needing quite a few stabs of the buttons to actually do anything, and then by locking the car every time I unlocked it, which wasn't fun trying to load shopping into it in the piššing rain (it got smacked on the roof rail for it's troubles). This one's a CR1616, I know for a fact that all I could get here is cheap crap from China, so I have a couple of Energisers winging their way from the bay of E. Until they arrive I'm having to do it the old fashioned way with the key (fortunately somebody was smart enough to lubricate all the locks a while back ) but I suspect it'll take me until the new battery turns up before I remember which way the key turns to lock and unlock it

[Bailes1992]

Additives!

I told you they were good.

[mjb]

Prove it.

You utter..... now I've got to wipe my tea off the screen!

[mjb]

Presumably it must talk to the key when its sitting in the ignition barrel and have a set parameter for the strength of the return signal???

No, the pcb in the key is only active when the button's being pressed. The aerial around the barrel powers the passive RF transceiver.

The key will likely transmit its battery voltage (or a good/low flag) when you press the button, along with the rolling code. This is how BMW keys do it, as reported by the equivalent of the BSI (from my ibus hackery):

Code: Select all

        elif cmd == 0x72:
            act = 'Remote unlocking status: '
            buttons = self.__bits2array(int(d[1],16) & 0b11110000, \
              ['', '', '', '', 'lock', 'unlock', 'open_boot', ''])
            keystatus = self.__bits2array(int(d[1],16) & 0b00001111, \
              ['bat_low', 'bat_ok', '', '', '', '', '', ''])

I also noted that a couple of those bits might be key id (1-4)

[Doggy]

How, prey tell, did you come by the source code?

(and can you find some in Puglish)?