CPU load increases & phone gets hot when in airplane mode

[d33p]

I took a 2 hour flight recently and put the phone in airplane mode.

When I landed I noticed my phone was fairly hot, the battery had lost about 40% charge and SysStats shows a constant 80-90% CPU load even with all apps closed.

As soon as I turned airplane mode off, CPU load dropped down to <10% and the phone cooled down.

I then isolated the trigger to data. If I disable data (cell and wifi), the CPU load jumps right back up and stays 80-90% and the phone heats up.

Turning data back on (either cell or wifi) causes it to return to normal.

I've done a soft reset and a hard reset. I've terminated all the apps in the background. All to no avail.

Any ideas?

 

[McGiord]

Is this jailbroken?

 

[d33p]

No, not jailbroken. Standard 4.2.1 build.

 

[d33p]

To recap :

if I turn all data off, processor load jumps right up, phone gets hot and battery life decreases massively.

if I turn data back on (either cell or wifi), processor load returns to normal, phone stays cool and battery lasts 24 hours.

 

[d33p]

Interestingly, whenever data is turned off, every time I go into my text messages I get a popup telling me to go into settings and enable data.

Why would simple text messages need a data connection??