C5 Headlights Come On Randomly

[hasher]

Hi My 2001 C5 Exclusive Estate HPi has started doing something odd. The headlights come on randomly. I can switch them off by swithing on and off. Is this likely to de electical such as the switch or electronic such as the ECU?

 

Also, my boot lights and the boot suspension height adjucting switch don't work, ever since I tried using LED rear light bulbs.

[Randombloke]

Hi My 2001 C5 Exclusive Estate HPi has started doing something odd. The headlights come on randomly. I can switch them off by swithing on and off. Is this likely to de electical such as the switch or electronic such as the ECU?

 

Are the headlights set to come on automatically? If so I would start by turning this off.

 

This may solve the problem. If it does it could be a problem with the light sensor.

[Guest accies]

Hi My 2001 C5 Exclusive Estate HPi has started doing something odd. The headlights come on randomly. I can switch them off by swithing on and off. Is this likely to de electical such as the switch or electronic such as the ECU?

 

Also, my boot lights and the boot suspension height adjucting switch don't work, ever since I tried using LED rear light bulbs.

Are you sure that you don't have automatic lighting?? :rolleyes: My Exclusive C3 had a sensor behind the rear view mirror which activated the headlights when it got dull outside. This can be disabled or re-enabled by one of the controls on the steering column. Check your handbook for this. You might just have re-enabled this without knowing it. ( It took me more than a year to find out that the Exclusive could switch it's lights on or off automatically!! :D

[coastline taxis]

Switch your ignition on then press and keep pressed the end of the light stalk youl eventually hear a bing and display will say auto lights on/off. if that dosnt sort it then id be thinking about replacing the com unit. Do you get a passenger airbag deactivated warning at all

[hasher]

Thanks for the replies. I also didn't know about automatic lights. I'm usually the first to put lights on anyway, so not as much benefit for me. They were not activated, but I have activated/deactivated and I'll see if the problem repeats.

 

I don't get the airbag message.

[seefive]

Thanks for the replies. I also didn't know about automatic lights. I'm usually the first to put lights on anyway, so not as much benefit for me. They were not activated, but I have activated/deactivated and I'll see if the problem repeats.

 

This is a fairly common problem on Mk1's and there are a number of posts on this site. I would say the auto light feature is acting up due to a failing comms unit, which will cost a few hundred pounds to fix.

 

A simple work-around which I used when I had a Mk1 was to drive on sidelights in the day. This overrides the auto lights and doesn't really do any harm. Sidelight bulbs are easy enough to replace. (unlike the Mk2!!)