Saxo Immobiliser

[muneeb]

Hi, I have a 1996 saxo 1.1 sx.

I recently took my car to to the garage to get the thermostat replaced as the cooling system was playing. While there the mechanic advised me to get the fan on the radiator changed, he advised me to bring the car in the next day to get this replaced. I was about to leave the garage when i realised my car would not start. The immobiliser keypad would not accept the code. The keypad was displaying red and green light both at the same time.

When working normally the keypad will display a flashing red light when engine is not on, and a green light when code is entered and engine is running.

Not able to start the car i left it at the garage. Since then the garage have tried several things to try and get the pad to accept the code as follows:-

-disconnect the battery for 24 hours and try pad again. This did not work.

-reset the code using 1111. this did not work either.

-mechanic thought maybe ECU issue, so he replaced this with another one. (he did not get the code for the new ECU as it was from brakers, who did not have the code). This abviously did not work

I spoke to Citroen dealers who gave me a quote on new ECU £495 plus VAT.

or to diagnose the problem £70 per hour.

The car has now been in garage for almost a month. I dont know if its the ECU, the mechanic does not know what to do and I certainly dont want to take the car to the dealers and get ripped off.

Any suggestions pls, really want to get to the root of the problem and get it fixed.

[Pleiades]

Try leaving the ignition turned on for about 1 hour, sometimes only 10 mins will re-set it but leave it for an hour and it should re-set.

Regards
Martin

[CitroJim]

There was a long discussion about locked immobilisers here. Sadly, no real conclusion was reached.

Although the thread is for a diesel, the immobilisers work the same on a petrol.

[muneeb]

have tried leaving on ignition for an hour. Didnt work. The problem is that both lights are on the keypad, which is not how the keypad normally behaves. Usually one light or the other is on. When the new ECU was put in only one light appeared as it should.

So im really feeling kind of lost here. Would recoding the ECU to my car help?/do I need the original code to of ECU to code to it to my car?/ is there any where I can get this coded apart from the "through the roof" dealers?

thnks

[wheeler]

I assume all fuses are ok ? Have you checked that the inertia switch has not been tripped (when the bonnet was slammed down) ?
If both lights are on then the keypad has lost comunication with the ECU, you need to get a pinout of the ECU & check that it's getting all its live feeds & earths. some of the feeds go to the ECU via the double relay under the ECU which if faulty can cause the ECU to loose feeds.

[Spud]

Have you tried disconnecting the battery for a while More than 24 hours may reset the electronics perhaps? It's worth a go and doesn't cost anything....

Good luck with it!!

Oh and reconnect the battery with the ignition on, it can prevent alarm/immobiliser problems too

All the best

Spud 8)

[red_dwarfers]

Now you talk about the communication issue wheeler, I do remember someone having a similar problem. Can't remember which forum it was to link to it but I do remember that the problem was solved by cutting the keypad end of the wiring a bit shorter and recrimping/soldering it due to a poor connection.

[wheeler]

was it maybe a synergie, because the keypad was on a flip down panel on some of these the wiring had a tendancy to break because it was being flexed all the time.

[muneeb]

Hi me again,

My saxo is still not working, way hay,

I have a new question. I now have an additional ECU

what i want to do is change the Memory chip from the old ecu to the new one. My father is an electronics engineer so he can do this. The only problem is i cant find any information on which is the memory chip in the ECU. PLease can someone help in advising which is the chip, maybe a chip number. Thanks