A rainy saturday sees me driving through the countryside when the keycode light comes on. [I now understand that's a diagnostic indicator?]. Anyway, as many of you will have already guessed, the battery had died, so after a jump start, I had a new battery installed, and car started fine at the garage.

But I get home - and no restarting. Code light comes on and stays on, and starting is lots of turning over, but no firing. Before anyone asks - its a 2nd hand car - and no red key.

Anyone know whats causing the problem. A quick fix would be especially useful - they are cleaning the gullys on Tuesday, and my car's gonna be towed if its still in the neighbourhood. Joy.

Will

dude, you may have problems with your ecu. no red key?:bang:

The red key will not help your problem. Have a look at the key and check that there is not a "2" near the logo on the blade. No "2" present = fixed key type. Because of the rainy conditions and wiring beig disturbed a thorough check of connections arouind the engine bay, especially for water around the ECU area.
Worst case scenario change immo + ECU, or change complete with locks etc s/h about £100.
System 2 (rolling code types) are more difficult involving in-car memory and control unit, and may need dealer intervention.

I read on another forum last night that disconnecting the reader sometimes solves the problem. last night I pulled some fuses to check if any had blown. They were all fine - and afterwards the car seemed to be working fine, and it started no problem.

This morning however, it started, then stopped, and I have the same problem with the code light. The code light sometimes goes out briefly, but even then the engine just cranks with no firing. Disturbingly, the code light sometimes goes out briefly if I move the wiring near the block of 4 fuses at the top left of the interior fuse bay.

Don't have a red key just an original and cloned blue key. Don't see any 2's - its a 97 brava, so probably not a rolling code. Last night, both keys worked fine again.

The battery people reckoned that if the battery connection isn't perfect, the low voltage can interfere with the immobiliser, but I have tightened the connections, and the car cranks perfectly well.

I can't rule out that it might be a damp related problem, since the weather was wet on saturday, and it rained last night too. I will try to check for any damp problems around the ECU. Once I've found the ECU - where is it?

Any other thoughts?

Will

if you had the red key i would have suggested reprogramming the blue keys into the ecu, however since you dont have the red key this isnt possible.

several times i've seen very similar problems occur after replacing a battery especially one that went flat and the car needed to be jump started. the blue key codes can be lost by the ecu during a battery failure.

however in your case this doesnt seem to be the cause, if the light goes out for a few seconds it suggests there is an electrical problem with the wiring or components of the immobiliser system, most problably due to damp. in situaitons where the key codes are lost i've never heard of the key code light going off for a few seconds.

personally i think you car will suddently start working ok for no apparent reason once it dries out. try to keep it in a warm dry garage for a few days if possible.

Thanks for your ideas, Jug

At the suggestion of a Fiat dealer, I tried disconnecting the battery for half an hour, but no joy on reconnection. Still get the code light going off intermittently, but the car won't fire, even if I try when the code light is off. Always possible this has made the situation worse...

I assume the ECU is in the grey metal box fitted to back of the engine bay, with the hefty vertical connection. It looks fairly clean, and completely dry.

I know the stereo has been incorrectly fitted (to the ignition circuit, not the accessory circuit), but this has never caused a problem before. Do you think I should try disconnecting the stereo entirely?

Unfortunately, no garage; warm, dry or otherwise...

Will

doubt the stereo has anything to do with it but its worth a try.

you found the ecu ok, but the immob circuit works on a seperate ecu, well its just a code box actually, but its located near the interior fuse box. its a black plastic lump, not very big. try wiggling the wires behind that. i have a feeling it may be wet or loose. or even try tapping it with a screwdriver.

I think I know the one - a black box about the size of 4 match boxes, with about 4 wires coming out the back of it. It is at the very top left behind the fuse cover panel.

It's dry, clean, and I have tried wiggling the box and the wires behind it. Wiggling the wires on the block of 4 fuses nearby sometimes "seem" to make the code light go out briefly - but its really difficult to be sure. All these fuses are OK - I have removed and replaced them all 1 by 1.

There doesn't seem to be anything loose on the code box, but it would be nice to remove it and replace it. Does it just pull forwards out of its mounting socket? I couldn't feel any regular connectors behind the mounting to disconnect and reconnect.

At times I have felt like giving this little box 'percusive maintenance' with something much heavier than a screwdriver. Doubt this would help my cause though!

Will

Oh - by remove and replace the code box I meant remove it and put the same one back in again...

Does sound like a poor connection problem as said before. Try looking around the interior fuse area because that is close to the immo box and give everything a thorough wiggle. If you suspect the immo is faulty and you want to replace it I can get the red key information for you to enable a new one or one from a scrappy to be installed.

yep thats the code box, its a while since i removed one on a bravo but i seem to remember one screw at one side to release it, and then the wiring connector on the back requiring a small screwdriver to relese the clip.

i think leaving it disconnected from the car for an hour or so is worth a try.

also try removing the upper and lower plastic shrouds from the steering column so you can access the receiver loop aerial. thats the part that reads the key code, if it wasnt reading the code you'd experience the same problems. disconnect it and check it over for any signs of damage such as loose or dmaaged wires.

Thanks for the ideas

I have removed the immo/code box, and left on the console for a while. Hopefully it will consider its position and cooperate. Have also removed the bottom column shroud - not sure how to get the top one off, and thus haven't located the loop arial yet.

The code light is still on - and occaisionally off for a second or five at random intervals. Everything looks tight, dry and clean, and poking and prodding various wires, boxes etc. hasn't given me any clues as to where the fault might lie.

Will

when you reomve the screws for the lower shroud the top one can be pulled off.

the reciever loop aerial is around the ignition switch (so it is as close to the key as possible). attack it

Hi all

Well, disconnecting the little black box for an hour didn't adjust its attitude, I'm afraid.

Actually found two further screws need to be removed for the top shroud. Anyway - found the loop antennae - a black plastic ring with a wire coming out the back - right around the key barrel. I unclipped it from the key barrel, and pulled it out slightly so it was right around the key - but no difference. Not sure how I can test the operation of the antennae - the cable doesn't seem to go directly to the immo box - but it does seem to be intact from what I can see...

The owners manual suggests that in the event of a fault "e.g. low voltage" the code light may come on while driving (which it was and it did). It further suggests that when the car is next switched on, the code light will come on in some way as a diagnosis. Does anyone know what the code light diagnoses patterns are supposed to be?

reddy4bed - how do you get the red key info - do I send you the said little black box and you interrogate it? Also, where does one go for a new immo box, and how do you program it into the car with the red key info? If you could send me a quick email with the procedure and costs, that would be great.

Have called the council - they tell me it shouldn't be a drama to get their drain cleaning truck around my car, so I'll put some signs in the windscreens - and cross fingers for my wing mirror.

Will

just a thought, i remember similar problems to this on a cinquecento and it turned out to be the alternator. combine that with the fact that your battery died and i think its worth checking out.

have you tested the alternator lately?

bravatwozero said:

The owners manual suggests that in the event of a fault "e.g. low voltage" the code light may come on while driving (which it was and it did). It further suggests that when the car is next switched on, the code light will come on in some way as a diagnosis. Does anyone know what the code light diagnoses patterns are supposed to be?

Click to expand...

the light will flash a certain number of times to indicate a fault, the number of times tells you the fault (well the type of fault, not exactly what it is)

Hi Jug

Good question about the alternator. When the battery failed on saturday, it was started by a service guy in a repair truck. He did test the alternator once the car started, and said it was producing 14 Volts or so, which sounded right to him and to me; certainly once started the car went fine. The new battery has an indicator imbedded in it which is still showing green - I've avoided cranking it excessively.

Couldn't say that the code light is "flashing" - there doesn't seem to be a pattern.

Other than trying to replace bits, I'm at a bit of a loss...

Will

I seem to remember being told the alternator should put out more than the battery.....but not positive on that. Check that your battery leads are intact and take off the connectors and vaseline the terminals. If the lead connector is looking crappy give it a clean, even roll up some sandpaper and give it a wiggle in there, get it nice and clean. Coat that in vaseline too and replace on the battery.
Sounds simple but may be something you haven't thought of.

Open the immo box and check for any dampness or signs of water damage inside if that is what you suspect - it pops open by pushing in the four latch pins on the sides. Btw, Disconnecting it and leaving for an hour won't do anything. If you are any good with a multimeter you could check its getting its power and a few other connections, but thats about it.

Owen.

bravatwozero said:

Hi Jug

Good question about the alternator. When the battery failed on saturday, it was started by a service guy in a repair truck. He did test the alternator once the car started, and said it was producing 14 Volts or so, which sounded right to him and to me;

Click to expand...

14.4v with no car electrics switched on and 14v with all electrics switched on is what you should expect, so if he tested it at 14v i wouldnt think there is a problem.

to be honest a diagnostics check at fiat is definately called for now, there's not much else you can do.