Hi all,
As the header suggests my problem is that I have basically lost all keys to my bravo. I managed to get in it and I have located the components related to the code system (Aerial, code box, ECU) but have not been able to start the car. So at the moment when I turn the ignition mechanism the key code light (yellow key) stays on.

THe ECU is a hitachi one and I was wondering whether there was a way of resetting this by earthing one of the pins and puttting a positive on the other or something like that.

I don't mind doing some soldering if required either. The way i see it is that the ECU is totally useless as it stands so no big risk there.

Any help would be much appreciated since Fiat have quoted a fortune and I am not too keen on these ECU modding places.

Thanks for reading and sorry for posting another key related question .

another one who's lost all their keys. i know its a bit late now but learn your lesson and keep copies next time. its £20 for a copy at timpsons so there's no excuse for not having at least 2 spares.

you can disable the immobiliser by modifying the ecu internals. from what i've heard you need to solder a wire across 2 pins on the ecu's PCB (hotwire the immob). i've seen it done on other cars (e.g. escort) but not on a fiat code system ecu so i dont know how to do it, but it can be done and i've seen compnaies offering these services on the net.

if you had a set of keys you could virginise your ecu and then program the new keys into it. but getting the ecu virginised will require you to send it off to codeman or another company offering similar services. i've seen people use the trick of passing 5v on the main ecu earth pin and then earthing another pin to wipe all the keycode memory on the ecu, effectively making it a new unused ecu (virginised) but i dont know which pin or if it definately works on the fiat ecu's.

its easier to swap all the bits over from a donor car. to do that you will need the ecu a set of keys that match the ecu (or at least the red key) and then you need a set of locks to go with it. thats the easiest quickest and cheapest option. finding a lockset with matching ecu and keys isnt easy, but the adtrader or ebay will no doubt have bravos bravas and mareas that can all be used as donors.

Thanks for your reply jug.

The once bitten twice shy thing applies to this case and surely once I get it fixed I will get spares.

With regards to modifying the ECU internals, I was wondering whether anyone had any specific info or even experience about that. Which terminals on the pcb etc. This solution would be ideal as it is a 10yr old car and its unlikeley that anyone would like to stael it.

Another good option you mentioned is this "ECU Virginising". I am now trying to find a wiring diagram to point out which is the ECU Main Earth Pin and I will try this method unless I get any further info on the previous method.

Regarding the complete ECU + Lock set there was one going on ebay but I missed out

Thanks so much for your support

if you do want to experiment with virginising your ecu it would help if you had a wiring diagram for the ecu. the diagram in haynes shows the main earth pin, and passing 5vDC on that pin is easy, but knowing which pin is connected to the memory for the keycodes is impossible without a detailed internal diagram, or careful inspection inside the ecu, or a lot of luck. thats as far as i got trying to figure it out myself. i didnt actually try guessing the second pin as getting the wrong one will almost certainly cause damage, athough 5v is less than the 12v of the car, a lot of the signals retuning to the ecu are lesS than 5v (such as sensor signals) so it would be easy to damage internal components. good luck

Re: Bravo 1.8 1996 **No Keys** Hitachi ECU

Hi Jug,
thanks for the support. By the way I made a slight mistake, the title should read 1.8 not 1.6 which I think makes this pretty much the same as yours. If you have that pin number for main earth pin handy in your haynes that would be great.:worship:

thanks again anyway.

i'm at work at the mo but i'll tell you when i get home

Hi jug, sorry I didn't reply to your message, I was away for the weekend.

Before you blow up your ECU dont try to do any earthing etc. The ECU cannot be erased in this way. What you have to do is start up the ECU in bootstrap mode, load a program into it, which allows a pc to talk to ECU, which can instigate a program to erase novram. So quite complicated and unlikely to result in any success doing it any other way. I can retrieve codes from some immobilisers, but dont know about your particular variety, What 8 pin chips does it have in it, I may be able to do something with it.
Tony.

i agree there's a great chance the ecu will be damaged, but reversing the current on any volatile memory will 'back-flash' it, wiping it clean. back in the days of nokia expession covers i used to work part time at the car boot sales selling mobiles (mostly insurance jobs), you had to wipe the phone's memory clean using the back-flash method prior to flashing the most recent software onto it to open all menus and unlock the phone. this was our way of completely cleaning the phone, erasing any record of the previous owner or company that originally sold the phone (except imei). so in theory it would work with any volatile memory, but very probably cause damage to the ecu. if you have a laptop with the appropriate software and wiring connector then i'd rather take that option.