Hi there!

2011 Skoda Octavia 1.6 TDI CAYC estate.

It was sat for about 6 months. Battery completely dead. Charger wouldn't charge it, so had to jump it. Let it run for a bit to get enough charge for the charger to work. Battery tests at 54% health now, good CCA, good voltage.

When the ignition is on, the radiator fan behaves normally. When the ignition is switched off, after about 30 seconds the fan comes on full, and does not switch off. When you then switch the ignition back on, the fan behaves normally again. I've timed it for 17 minutes going after the engine is turned off and key removed. I've disconnected and reconnected the fan. Connectors look clean. Fuse box looks clean. I've tried it with the radio removed due to radio fault codes, no different. If I leave the battery disconnected for a long time (hours), the fan doesn't come on when it's reconnected, until you turn the car on and run it, and then turn it off again. Coolant temperature reads perfect through my scanner and correlates to the dashboard dial (as much as they do in these cars).

4 fault codes. Seemingly unrelated.

01134 [046E00] Alarm horn - No signal/communication

02394 [095A00] Bulb for left front parking light - Open circuit/short circuit to B+

01304 [051800] Radio - No signal/communication

01044 [041400] Control unit coding error

The radio is after market Chinese tat, so that explains the second 2. I'm not sure if the first 2 could be affecting the signals to the fan. I'm a bit stumped on this one. With the fan disconnected I applied 12v to the fan it's self, and it did not spin up, so I feel it's not the fan, but the messages it's receiving.

Any ideas anyone?

Thanks for your time!

Greg

In a situation where I had the same radio and comms faults, I disconnected the battery, left it for 10+ minutes and reconnected the battery. All faults gone.

Give it a try as it may fix the fan problem too.

My thought is that if the battery voltage gets too low it screws up some stored settings and then needs the equivelent of ctr/alt/del.

1 minute ago, pikpilot said:

In a situation where I had the same radio and comms faults, I disconnected the battery, left it for 10+ minutes and reconnected the battery. All faults gone.

Give it a try as it may fix the fan problem too.

My thought is that if the battery voltage gets too low it screws up some stored settings and then needs the equivelent of ctr/alt/del.

I actually can't leave the car with the battery connected at the moment, so I've been effectively doing this every few hours. I also tried crossing the terminals to discharge capacitors. I'm wondering if it thinks it's mid dpf clean and is stuck in that state? Might be worth me taking it for a long hard drive perhaps?

Cheers,

Greg