General Unusual CODE Problem - Bravo HGT

[mountainmachine]

Hi mate having a bit of a problem at the mo, my Bravo HGT X Reg has been off the road for a few months while waiting on getting some stuff done.

It had been started etc most weeks.

However went to start it last week and the key code light remained on, bugger i though, went home looked for the red key (which i have somewhere) but cant find it! Tried the other blue key today and same problem. I thought the keys lost the code not the imob lost the keys, hence why i thought the other blue key should work.

Waiting on fiat getting back to me about the emergency start code etc. But as usual they're being slow and not returning my calls.

Now what are my options? I know you do some work on decoding etc.

Ideally if worst comes to the worst i'll try and get a replacment ECU, but that means, alarm ecu, locks etc. And getting one for the HGT is a bit tricky as dont know if the 20v Marea ECU is cross compatable.

If i was to get my ecu decoded would it be able to be recoded when i found my red key? I'm in the process of trying to find it just now, but if i dont by the end of the week i'll need to do something. Thankfully i have another car at the mo.

Its usually the immo that looses the key code, the keys never go wrong.
It is unusual for the later immo's to become corrupted because they have a mirror copy of the data and checksums, so if one image loses some data then its copied across from the good one to tha bad one.
Similar system operates in the later ecu's.
I haven't a copy of the wiring on that model, but think its well worth a fuses, relays, connectors check.
I can test out the key to immo compatability and operation, but not the immo to ecu without the wiring info.
Let me know if you want any more help.
Tony.

Now cant find this in the search as to which fuses/relays etc to check, as the cars not at mine i want to go prepared with a list of stuff to check. Here's what i've found, although only thing it tells me is which fuses in the dash to check, i'm not sure what relays etc.







If i've missed something from the Key Thread, please point it out.

Images from the marea manual as cant find the 20v wiring in the Bravo/a manuals.

 

[jug]

you will probably fix it by giving the codebox a good wiggle (131 on diag), also wiggle all the wiring around it, and thump the ignition switch, its usually a bad connection at the ignition switch aerial (199 on diag) or the codebox.

an orange light suggest the immob has power, this is confirmed by the wiring diagram, it was only the system2 models that can illuminate when the power fails, so i do not think the fuse is a possibility.

funnily enough this problem is also common on the 156. at least fiat are consistently crap.

 

[wigan_muncher]

hey just notices your prob it could be a number of things. on the 1.6 bravo if you get the engine ecu 'virginised' in a way like a new one is with no stored code then you can get the car started if you DISCONNECT the code ecu BEFORE turning the ignition on (the code ecu wont give the engine ecu a code to store) just wondered if it would work on the 20v surely worth a try if your desperate

 

[jug]

i think you mean decoding the ecu to disable the immob. that can be done if you send the ecu away to somelike like tony (reddy4bed), but there's no need to disable your immob if its just the usual bad connection that is the problem.

 

[mountainmachine]

Ok so i've not been able to get to the car due to other commitments, however my friend who's house its at and who knows a bit more than me in some aspects got it started, but only by disconnecting the battery for 5 min starting it, then to restart you have to do the same thing again.

 

[mountainmachine]

Ok so i've not been able to get to the car due to other commitments, however my friend who's house its at and who knows a bit more than me in some aspects got it started, but only by disconnecting the battery for 5 min starting it, then to restart you have to do the same thing again.

Ok so went over today, it starts when the battery's reconnected after disconnection. Code light goes off and starts as normal.

When you switch it back off, and go to turn it back on the code light illuminates and stays on.

Now as its starting sometimes, and not others i'm stumped! I check the fuses for the CODE system, gave the aerial a bang, tried the fuel cut of switch, and tried bridging the cut off switch. Non of that changed anything.

Went in to my fiat dealer to get the codes, wouldnt get them for a few hours... fine... phone call to say they couldnt get them, perhaps they had to be ordered through parts. Parts cant find any mention of how to order them on their system, so told me they dont exist! I questioned this so, their meant to be checking with HQ tomorrow...

 

[jug]

the battery reset trick suggest your problem is an immob ecu fault, but i dont like suggesting things like that so lets just pretend its not happening and instead wire a switch to your battery earth that you can operate from the driver's seat. very motorsport, suits you sir.

 

[mountainmachine]

the battery reset trick suggest your problem is an immob ecu fault, but i dont like suggesting things like that so lets just pretend its not happening and instead wire a switch to your battery earth that you can operate from the driver's seat. very motorsport, suits you sir.

Any way to test this?

 

[jug]

yeah, run a diagnostic on the immob ecu. fiat examiner only i would expect.

 

[mountainmachine]

Right going for a look round the scrap yards tomorrow, what parts would i need if i wanted to replace the whole imob system with a new one? Would a 155 20v Marea ecu etc be compatible?

 

[reddy4bed]

It does sound to me like an immo ecu problem.
If you had the red key you could put a new immo in, but i assume you dont have it.
Because it works sometimes it would be possible to extract the red key code . without stripping down the immo. You can then make a temp red key card and load keys into new immo as above.
If you want to go that way I can make up and loan you a red card/key to help out.
Alternatively the codes from old immo can be transferred to scrappy immo, but that takes a little time. (about 1.5 hours).
Dont know about compatibility of ecu etc.
BTW whats the No's on the immo ecu?.

 

[jug]

you'll only need codebox, ecu & red key chip.

 

[mountainmachine]

Found my Red key today... :slayer: does that mean i can try do anything different? The engines dismantled at the moment, so cant do it today but does that give me more options? Was hiding behind on of those wee callanders on a key hook i'd forgotten was there.

 

[jug]

try using the red key, if the code light switches off then you are laughing and can teach the codebox your blue key codes. if it doesnt work then you have an immob system fault.

every second use of the red key will keep the code light switched on (to show you've done a bad key sequence in the programming procedure) so dont be concerned if that happens.