Issue with dashboard needle for temp gauge and other components such as rear windscreen wiper

[Steve89]

Hello ladies and gents. 

I wonder if someone would be able to point me in the right direction, I have a 2007 avensis D4-D t180. 

Today, driving home from work, my temperature gauge needle slowly raised itself to its normal temperature reading as normal, 2 minutes down the road and then it drops to the bottom of the gauge and a few minutes or so would return to its original position, further down the road, my rear windscreen wiper turned itself on without me needing to turn the switch. There's been few days of constant rain and there has been a little leak coming through the roof so I'm not sure if its a water leak related issue which has cause wires to corrode and cause this fault. 

Any information is valuable. 

[Ashsnaaap]

Hi Steve,

Did you have any luck finding out what the issue was? I'm having the exact same problem (2005 t180)
Car parked in the rain overnight a couple of days ago (normally in the garage) and then tonight this happens:

• AC stops working (windscreen instantly fogs up on motorway)
• Temp gauge goes to zero
• Rear wiper turns on and stays on constantly
• Fuel/trip computer display thing turns blank but still lit

I noticed there was a little bit of rust around the windscreen and potential water leak inside and into the dash area, definitely sounds like our issue is caused by water ingress.

I'll be taking a better look around the fuse box area tomorrow but if you have had any luck solving this issue and can point me in the right direction it would be really appreciated!
 

Ash