insomniak

Hi, I have a 2001 Focus Zetec Automatic 1.6. I had been having some problems with the transmission where as the car seemed like it was pulling away in 2nd gear so was generally slow until you got up to around 15-20mph, anyway I decided that I would disconnect the battery for a few minutes as it could reset the ECU and might fix the problem without expensive repairs.

After reconnecting the battery I started the car and drove it for around 5 minutes, the problem was still there so I parked up and left the car for a few hours. When I returned to the car I put the key in the ignition and it would not turn over, so I tried setting the alarm, unlocking etc then trying to start again and the same thing, the immobiliser is not deactivating.

The PATS light stays on when the key is in the ignition and turned to the "engine on" position, after about 2 mins it goes out and then flashes twice, then once then repeats the sequence. I have since discovered this is a "PATS Code 21" and it means that there is less than 3 keys programmed to the vehicle.

I only have 1 key for the car, and i'm pretty sure its not the master key as its one with the 3 buttons on.

I have tried leaving the battery off overnight, keeping the terminals connecting to apparently clear any static in the ECU but I am still getting the same thing.

I took the key to local garage and the guy tested it on a machine and said the key seemed fine, so it cannot be a damaged key.

Does anyone have any others ideas?

Anyone in the UK from the Essex / Romford / Dagenham area that has some diagnostic equipment or who can cut & program new keys for a good price, please get in touch.

insomniak

Following on from the above, can anyone tell me if its possible to put an ECU from another Focus of the same year onto mine without it requiring programming or anything?

Does it matter if the car it comes from was a manual and mine is an auto?

I would be getting a paired ECU & Transponder (Key Fob) so hopefully that would sort the immobiliser issues. Lastly is the ignition barrel ring (chip reader) required or is that just a generic reader that can read any ford key?

martysmartie

iTrader: (1)

It does yes, and they probably have different part numbers, as the auto transmission is controlled via the ECU.

If you have the correct partnership for the other ECU, then the immobiliser will be disarmed, and it may even start but won't run correctly.

No the aerial merely reads the key, it's not unique!

There are only 2 keys as anyway, you have the remote key and the conventional key.

The key programming is DIY!

Martin

insomniak

Thanks for your reply,

I am having trouble finding an exact match, the 4 digit code on my ECU is "RENT" and theres none about on ebay and i've put a request in on a national spares website to see if anyone has one, but I'm guessing some breakers yards may just sell me any ECU.

Do you know if it matters if the vehicle it comes from is an estate or saloon, as mine is a hatchback, as I may just have to try an ECU from a 1.6 auto without it being an exact match.

insomniak

My current ECU part number is: 1S4F12A650PB RENT EECV LP2-320

insomniak

Today i've put new earth cable and changed the negative terminal connectors and it's not helped.