This may be common knowledge to some But at this time of the year (freezing temps taking its toll on car battery's) I thought i would reiterate what may happen when you remove/replace your battery......
...I had decided to change my battery today (mainly because the non standard & wrong fitting battery on my GS was sounding a bit tired, having stood for the past 3 days in these freezing conditions we have) and i took advantage of a good deal at Halfrauds on a Calcium 4 yr Guarantee 540 amp battery that was specified for all the GS range...(top quality batteries made by 'Yuasa'!...£92)
....Simple job....But on refitting, i found that i could not start the car as the Immobilser was not recognising the 2 keys i had (one being the master key!....ALL other functions/open/closing doors, alarm set etc were working fine!!!)....Now i was sort of half anticipating something might be an issue upon changing the battery But having got to grips with re-programming a spare key recently and having a good mechanical apptidude, I figured i could sort it !!
Well, to cut a long story short (going through re-programming proceedures, checking relays /fuses, re-connecting battery again etc..) I was at a Loss
......I was contemplating ringing My Lexus dealer....
.......Then, having left the Ignition key in the 'ON' position (NOT 'ACC' position) for about 4-5 Minutes, removing it & then re-inserting........BINGO! the car started
I guess this is the cars ECU taking its time to 'Recognise' the key in the ignition ?
Appologies to those that are aware of this fix and they may be the solution somewhere on this forum but i hope it is usefull to someone in the future who gets a bit baffled, as i did !
Cheers & a happy new year, Phil