Keypad immobiliser

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Keypad immobiliser

Post by colin.dibley » 01 Oct 2003, 02:19

<b>Keypad immobiliser</b>
My keypad immobiliser has suddenly developed a fault (as indicated by illumination of both green & red leds on the keypad). Peugeot 406 LX (’97).
The immobiliser continues to work, but often requires the input of the code despite being set in automatic mode (i.e such that it should not be necessary to enter the code providing the engine is started within 1 min of unlocking the doors). While it is still working, I have taken the precaution of disconnecting it (in order to avoid it packing up altogether & perhaps disabling engine start!).
I have 2 questions relating to rectification of the problem:
1. From my simplistic understanding of the wiring diagram, it would seem that the keypad simply provides a ground for injection relay signal when the immobiliser is enabled (engine start inhibited). I assume that my understanding is incorrect, since I figure it can’t be as easy as this – since simply disconnecting the keypad would bypass immobilisation?
<i><b>Any clarification on functionality of the keypad appreciated!</b></i>
2. I’ve been to the scrapyard & got another keypad. It came off a Xantia; unit looks fairly similar, but there are obvious construction differences inside, when comparing with my original keypad. The multi-way connection seems the same, & the only superficial difference is that the original keypad annotates one button as “S”, while on the Xantia keypad, this button is marked “D/N”.
I haven’t dare connect up the replacement keypad for fear of causing damage (e.g to engine ecu where I understand the 4 digit code is stored).
<b><i>Anyone know if these keypads are interchangeable?</i></b>
Thanks in advance to anyone who can provide any help!
<hr noshade size="1">
colin.dibley P406 LX, 140k miles; BX16 TGS, 225k miles<font face="Arial"></font id="Arial"><font size="6"></font id="size6">

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Post by andycarter » 02 Oct 2003, 01:33

The xantia handbook shows 2 types, one with a D/N button and the other (like mine) has a C button and an S button.
Can't help you re: interchangeability, and I didn't know about this 'automatic' mode.
C = Change Code
S = Enter Service Mode (e.g. 2nd code you can give to someone, but they can't change your original code)
D/N = Defer/Neutral (could that be the automatic mode you're refering to?)

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Post by blueboy2001 » 02 Oct 2003, 03:04

If you're not bothered about having the keypad, enter the correct code, start the engine and leave it running and remove the multiplug from the back of the keypad.
It will never bother you again.

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Joined: 26 Feb 2003, 17:33

Post by IAN.D » 07 Oct 2003, 23:18

You can use key pad from another car as long as you get the same one.
The one you got from the scrap yard will have been from an early xantia as these as well as the peugeot used to come with the one marked D/N, later cars come with the one marked "S"
If you can get one with the same marking as your one you can just disconect the old one and conect the new one and it will operate like normal (the code is stored in fuel injection computer so will still operate on old code)
If corect key pad does not solve problem must be an electrical fault else where.