Alarm/ Immobilizer cutting car out whilst driving

[crashbanggg]

The last two times I have driven my car, the Alarm has gone off and the immobilizer has killed the engine, once when I had to do an emergency brake at about 60mph and again today when I hit a small bump in road. To turn the alarm off, I had to get out and disconnect the battery both times. However today, it simply would not work, as the alarm would go off as soon as I shut the door/ bonnet and cut everything again.

This has only happened since installing my sub, which I guess must be at fault, especially since it appeared to work alright once I had removed the sub's power cable from the battery. So why could this be/ what have I done wrong?

The sub was wired in by unscrewing the bolt on the battery terminal and sliding the ring connector on, then bolting back up:


And the amp for the sub is earthed as such (If that would have an effect?Though the sub/ amp work fine when the car is going):


Oh, and the alarm randomly went off whilst sat on the driveway (I have never actively turned the alarm on, im not even convinced the motion sensor is connected)
What have I done wrong?!

Cheers

Chris

[ianaudia4]

Try disconnecting the amp. Check every accessible earth and clean up if necessary.
Does sound like you have upset the system by fitting the amp.

[Jack92]

Where is that earthed to? As it could well be an earth issue causing it. Maybe just find a better section of metal (not coated in anything)

[crashbanggg]

I'll have a check over some bits tomorrow. It's currently earthed to my parcel shelf clip bits (Which is aluminium with a bolt securing it in place), but I might switch it to the rear seatbelt plug connectors as that looks a bit more 'raw' for the metal contact.

[ianaudia4]

I'll have a check over some bits tomorrow. It's currently earthed to my parcel shelf clip bits (Which is aluminium with a bolt securing it in place), but I might switch it to the rear seatbelt plug connectors as that looks a bit more 'raw' for the metal contact.

Obviously a very poor earth! Take an earth from boot light switch but connect it properly!

[crashbanggg]

Aha, it's becoming clearer day-by-day how much of a n00b I am at all this!

[ianaudia4]

Just ensure you don't bodge, this is obviously why you are having other electrical issues mate.

[crashbanggg]

I connected the earth to the earth used for the rear lights and have successfully commuted to uni and back without any trouble! Now to try and fix my wipers!

[ianaudia4]

I connected the earth to the earth used for the rear lights and have successfully commuted to uni and back without any trouble! Now to try and fix my wipers!

Glad to hear it. Worthwhile checking your earth strap from the coil to the block.