PA100 odd behaviour

[Johnny C]

I was putting the car away before going on holiday, just locked it and the alarm went off, I think because I had the bonnet open to disconnect the battery. I reset it by opening the door with the key which worked, but it instantly locked itself again. I tried again, and the same happened. So I disconnected the battery and shut the bonnet and went off for 2 weeks.

I thought that by having the battery disconnected for 2 weeks it would reset everything.

I came back, opened the door with the key, reconnected the battery, shut the bonnet. locked with the key and tried pressing the fob to unlock. The alarm went off. So I unlocked with the key, the alarm went off but it locked the door instantly again.

I tried again, the same happened, door unlocked but then relocked.

Just on a whim I went to the passenger side and unlocked it, and it was fine. I tried the fob and it worked, the lights flashed a lot of a few seconds but since then it has been fine.

However I have had a couple of run ins with odd behaviour of the alarm (which goes off randomly every few days if the fuse for the inside lights blows)

I am hoping it's just some weird design idea that if the bonnet is open to potentially do some mischief when the car is locked, it decides that no-one is getting into the drivers side and unlocking via the passenger side resets it.

Any ideas?

Cheers

 

[Mark Elder]

This sounds similar to a problem I had back in March/April (which I posted on here but now can't find). Car would randomly operate alarm/remote type functions and it appeared to be related to the bonnet sensor (but only "related" because I eventually discovered that symptoms persisted even with the sensor completely disconnected). Sometimes locking the car would only last for a second or two and it would unlock again. I never noticed the passenger side being different from the driver's side (but I might not have tried). Alarm would randomly sound. But then it would be fine for a few days.

Outcome was: I discovered condensation in the main (front) fuse/relay box - was not obvious but removing a relay revealed damp under the relay. I removed others and found more.

So I purchased a large (1kg) bag of desiccated crystals and left it under bonnet with the top off the fuse box for a while. After several weeks I realized I was no longer seeing the problem. So (I think) problem was lack of driving / weather conditions last winter causing condensation on electrics. For various reasons I didn't drive the car from summer 2018 until March this year. (So there's an easy way to fix that!)

My fuse box cover doesn't fit particularly well. It has always been like that. But that might have allowed moisture in the air to get in - although I doubt it is sealed underneath.