Can anyone help? I replaced a dead battery with a brand new one back in February and I have had nothing but problems with the Car Alarm on my 1.9 16v Croma. I even had the alternator repaired and yet still having the same issues with Alarm. I even kept the doors unlocked after the alarm went off and guess what? Alarm went off to my surprise. I had no issues with the alarm even when my old battery was dieing. My only guess is ECU as why would there be a sudden power drain once I replace the battery. I'm out of ideas, can anyone help?
Technical Car Alarm issue
- Thread starter Holdo15
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Technical Car Alarm issue
It's probably a dodgy alarm sensor somewhere that's making it think there's been a break-in when there hasn't.
Does anyone know if the alarm keeps a history of what triggered it, and whether you can query it with ECUScan?
In the meantime, do you have the buttons that allow you to disable parts of the alarm? Mine are in the centre of the roof at the front.
The one with a picture of the car being towed with a big hook disables the movement sensor. Try pressing this before locking it for a while and see how it behaves.
Then try locking it after pressing the other one - I forget what its icon is. This disables the interior movement sensor. It's what you should press if you leave a person or dog locked in, so they don't set it off. After trying the tow-away disabling above then try locking it after pressing this.
Your results should give an indication of where to start looking.
Finally, do you have a sunroof? If so then I know someone else here had issues with a loose sunroof setting off the interior movement sensor (as it would).
I'm thinking the battery change may be a coincidence, or perhaps the power cycle made a dying sensor die a bit more.
I think some scientific experiments over a good few days are needed.
Does anyone know if the alarm keeps a history of what triggered it, and whether you can query it with ECUScan?
In the meantime, do you have the buttons that allow you to disable parts of the alarm? Mine are in the centre of the roof at the front.
The one with a picture of the car being towed with a big hook disables the movement sensor. Try pressing this before locking it for a while and see how it behaves.
Then try locking it after pressing the other one - I forget what its icon is. This disables the interior movement sensor. It's what you should press if you leave a person or dog locked in, so they don't set it off. After trying the tow-away disabling above then try locking it after pressing this.
Your results should give an indication of where to start looking.
Finally, do you have a sunroof? If so then I know someone else here had issues with a loose sunroof setting off the interior movement sensor (as it would).
I'm thinking the battery change may be a coincidence, or perhaps the power cycle made a dying sensor die a bit more.
I think some scientific experiments over a good few days are needed.
Thanx for your reply. I don't have a sunroof but I do have both those alarm sensors you talk about. I'm gonna give those a try. It would be great if the ECU records which sensor is causing the issue.
Last resort is take it into the fiat garage as god only knows how much they will charge just to let me know what the issue is.
Last resort is take it into the fiat garage as god only knows how much they will charge just to let me know what the issue is.
I'd hazard a guess (from my bitter experience of dealers) that they won't know what the issue is and will just replace every component of the alarm system until the problem goes away, charging you every step of the way.
It wouldn't do any harm to check your battery voltage, both with and without the engine running. Also check the voltage straight after it next goes off, without starting it.
It wouldn't do any harm to check your battery voltage, both with and without the engine running. Also check the voltage straight after it next goes off, without starting it.
I havent took it in to the Dealer yet. Was too afraid of the costs. Just a quick question, would A), jump starting the batterys cause any issues with the ECU and B), Would the lack of power from having a dead battery in the car for a few weeks cause any issues with the ECU?
Also I heard someone mention water in the loom. Not even sure what/where the loom is.
Also I heard someone mention water in the loom. Not even sure what/where the loom is.
Theoretically taking the fuse out won't stop it going off as it should have a back up to stop the battery being disconnected. Jump starting it incorrectly (you should connect the cars positive to positive and then the negative terminal to an earthing point on the Croma, not directly to the battery) can cause all sorts of problems. Did you eliminate the interior and anti tipping sensors? The most likely sensor to go is the one on the bonnet catch, so I'd start there.
Good luck.
PS if the ECU knows which reversing sensor is faulty, I would be very surprised if it doesn't log which sensor is setting off the alarm.
