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The NC wouldn't start for my wife this morning, she thought it was the battery.
So, when I got home I tried to start it but the starter just clicked and the dash lights flashed. I checked the battery terminals and they were loose and had some grease on them. Cleaned them up and tightened the terminals and the battery bracket which was also loose.

I was able to start the car straight away, but the idle is slow, the headlights came on and stayed on and I can't turn them off, and the DSC and traction warning lights on the dash stay on.

Any help would be greatly appreciated.

Sam

2007 NC PRHT 2.0 litre, 6 speed manual, stock standard except immobilizer/alarm fitted - don't know if it's genuine or aftermarket.

There is a procedure to reset the DSC/TC - see the Owner's Manual.
Can't help you with the headlights stuck on issue.
You may need to get a fresh battery.

Thanks JBT, I'll reset the DSC now.

The battery is fine. 12.5 volts. It's only charging at 13.8v though, but that's at low idle.

That charge rate seems OK.
Something must have been fried (relay or control circuit) if you cannot turn the headlights off.
Low idle sounds like the ECU has reset or something has fritzed in the system there too.
If it doesn't come good with a charge up, you might be best to go to an auto electrician.

I am with JBT re: The headlight issue.
When the circuit was trying to sort itself out around the intermittent power supply, there is a possibility that the headlight relay was opening and closing rapidly and with enough energy to build a carbon film over the contact points, which may have caused a fusing of the points or a current loss. My car is somewhere else ATM but I am sure that there will be a similar relay in the block, swap them over and see what happens.
Greg.
P.S. Keep us informed.

Any chance you have an auto headlight setup?
Might be the reason for the headlights on if it's in the garage

yep could be the Auto lights if you have them on your car.

As for resetting the DSC, start the car and then turn full lock to lock both ways, turn the car off and then restart, that should sort the lights out

No auto lights on the car. I'll try swapping the relays.

Wife's on holidays now (teacher), so we can make do without it for a while.

I'll keep you informed.

Sam

So, here's the latest:

Fitted brand new Century battery - charged on brand new charger for 2 hours before fitting.

Started car, reset DSC and traction control warning lights.

Idle is still low and the headlights came on and stayed on. Couldn't turn them off.

Took it for a drive - about 5 k's and when I got back the headlights turned off.

Then the wife took it for a drive, about 40 k's round trip.

When she got back the lights turned off, but when she turned the car off and got out, I turned the car back on and after 3 seconds - the headlights came back on again and won't turn off.

I'm stumped.

take it to a professional for diagnosis.

Just to double check.
Do you have a little thing that looks like an LED about 8mm dia at the bottom front of the drivers side A pillar plastic cover..inside of course?
This is where the sensor for auto lights lives.

SOLVED!

Sailor, it does have the sensor. So, it is auto lights. But there's nothing in the manual about it.

And, I found out how to turn off the auto lights. Quickly turn the headlight switch from off to on, twice. That turns it on and repeating that sequence turns it off.

Thanks for your help.

Sam