My low beams don't turn off even when the ignition is off and keys are out. they just remain on. what is the problem?

The headlamps may be turned ON in 2 different ways. First, when the driver places the headlamp switch in the HEADLAMP position, for normal operation. Second, with the headlamp switch placed in the AUTO position, for automatic lamp control (ALC). During ALC the headlamps will be in DRL operation in daylight conditions, or headlamp operation in low light conditions.
Headlamp ON/OFF control is determined by the body control module (BCM) by a signal on the headlamp switch on input circuit when the headlamp switch is in the HEAD position. When the headlamp switch is in the AUTO position, the BCM determines headlamps ON/OFF by the voltage from the ambient light sensor.
If the headlight switch is left in the ON position, the inadvertent power control feature will turn OFF the headlights approximately 10 minutes after the ignition switch is turned to the OFF position. If the driver places the headlight switch in the ON position after the ignition switch has been turned OFF, or if the ignition switch is in the ACCY position, the headlights will remain ON until turned OFF or the battery runs dead.

Low Beams - Standard
The low beam headlamps receive voltage from the headlamp low beam relay located in the underhood fuse block. The BCM controls the relay on the headlamp low beam relay control circuit. Low beam control is determined by a signal on the headlamp dimmer switch signal circuit from the multifunction switch. When the headlamp dimmer switch signal circuit is open, the BCM grounds the headlamp low beam relay control circuit, illuminating the low beam headlamps. The right and left low beam circuits are independent are fused independently in the underhood fuse block.


Do you know how to test electrical circuit's - relay's ? How to use a digital voltmeter ?

First check light relay fuse, if ok check battery voltage at low beam light terminal, if ok replace low beam bulb, if no voltage check switch side of relay, if voltage replace relay, if no voltage check headlight low beam switch.

check headlight relays

Hi I had this happen last night but both of my headlights were out (one had been for a week but the other also went last night) I assumed it was to tell me there was a fault as it's stopped now I have replaced the headlight bulbs

The wiring for the low beams would run not to the ignition, but to the dimmer switch. I don't know what color they are, but sounds like you are at the source of the problem, if the low beams quit when the column is let down. Pull the trim pieces off the steering column and examine the wires going to the dimmer switch. You may see some wiring insulation scraped off. It could be a bad dimmer switch, but check the wiring first.
Good luck.

iTS A FAULTY HEADLIGHT SWITCH

i think im right in saying the low beam bulbs are twin filament(low and high beam in one)and the main/high beam are single filament(spotlights).

NOTE: If a double audible warning sounds during the programming procedure a system malfunction has occurred. Repeat programming procedure.
Obtain all keys fitted with remote control. Open driver's door. Operate headlamp high/low beam switch to flash high beam position and hold. Insert key into ignition switch, turn to ACC position. Ensure system LED flashes once and an audible warning sounds. Operate headlamp high/low beam switch to flash high beam position 5 times. Ensure system LED flashes once and an audible warning sounds. Programming mode activated: Press and release lock or unlock button on first key. Ensure system LED flashes once and an audible warning sounds to indicate correct programming. Repeat programming procedure for remaining keys. Switch ignition OFF and remove key. Close driver's door. Check operation of keys. Keys can also be programmed using diagnostic equipment.

: If a double audible warning sounds during the programming procedure a system malfunction has occurred. Repeat programming procedure.
Obtain all keys fitted with remote control. Open driver's door. Operate headlamp high/low beam switch to flash high beam position and hold. Insert key into ignition switch, turn to ACC position. Ensure system LED flashes once and an audible warning sounds. Operate headlamp high/low beam switch to flash high beam position 5 times. Ensure system LED flashes once and an audible warning sounds. Programming mode activated: Press and release lock or unlock button on first key. Ensure system LED flashes once and an audible warning sounds to indicate correct programming. Repeat programming procedure for remaining keys. Switch ignition OFF and remove key. Close driver's door. Check operation of keys. Keys can also be programmed using diagnostic equipment

Also, the daytime driving lights are controlled by relay. It's possible the relay may have melted down inside and is shorted, remaining on even when primary ignition power is off. The relay runs about $15.00 to $20.00 USD and might be worth a shot to replace. Likely you can get one at a recycling yard for a dollar or two.