Our Volvo XC40 Recharge decided to go into ‘night mode’ the other day, which made the instrument panel impossible to read in the bright sunshine. Yes, we do have bright sunshine sometimes in Scotland!
After getting home my wife found a dim enough place to read the display, and turned up the brightness, but it still wasn’t ideal. We then noticed that a strange bright U-shaped red LED was flashing on top of the dashboard, in the centre where the little red ‘dot’ normally blinks when the vehicle is locked.
There’s nothing in the manual about this light, and nobody seems to even know what it’s called, which makes it hard to explain to people what the problem is. Part of the problem is that it flashes all the time, whether the car is locked or unlocked, and when it’s being driven. That’s a problem because it’s clearly visible at night if you stand in front of the car and, at least in the UK, it’s an offence against the lighting regulations for a motor vehicle to show a red light to the front. That makes it technically illegal to drive.
Various searches online produced no helpful advice, I suspect because no-one can describe the problem well enough when the ‘funny light’ has no proper name. We tried resetting the system, and powering the car on and off, and various people said it was something to do with the alarm – which it turns out not to be.
She had a chat dialogue with Volvo on the app and they suggested various things, none of which worked.
To cut a long story short, the car finished up at the dealer, who was very helpful.
It’s a relatively new car and they didn’t know what it meant either, but their diagnostic tests revealed that there was a fault with the ambient light sensor, which we discovered is apparently called the “sun sensor”. That is in the little blob on top of the dashboard containing that light. The manual ought to tell you that otherwise you might put a book or a folder on top of the dash and cover it up.
It was a simple warranty repair which involved a return visit because they had no spare at the dealership.
This sensor determines the ambient light level which controls the day and night mode, which is obvious once you know that because if you cover it up with your hand the instrument backlighting goes dark. Anyway, they tell me the vehicle is perfectly safe to drive until it’s fixed provided you remain aware that it might affect the auto headlights. If it think its dark during the day and the car goes into night mode it may turn the headlights on unnecessarily, which is not big deal, but if it doesn’t realise it’s dark it won’t turn them on automatically at night. So – you might have to use the switch instead. Unfortunately, there is no instrument panel lamp to indicate whether the headlamps are on or not, only a single green one that means ‘lights’, so unless it’s properly dark you might not be able to tell, and there is no way to tell what position the little rotating light switch on the stalk is in without looking at at because there is nothing on the instrument panel to tell you, and the legends on the stalk are not lit. That means you might have to stop and turn the interior light on in order to see what the lighting switch is set to. Some improvement in usability needed here I think.
Until it was fixed we covered it over with the cloth we use to wipe the inside of the windscreen, to avoid attracting the attention of any traffic officers.