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Have Your Iq Headlights Turned Themselves Off Whilst Driving?


onboardvision
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As the heading says.

My daughter who is using this car at her home town around 50 miles away is reporting that she was flagged down yesterday in the evening to be advised that her front lights weren't on!

She didn't notice? Anyway, she had the lights in auto and turned the car on and off a few times and the lights came back.

Now the bad part of this is the car is fitted with 35 watt HID's

I'm now looking for a wiring diagram or some inspiration as to the possible cause.

Looking at what i have found so far, all the lamps are fused separately and have relays, Its improbable that the HID's went in to fault simultaneously so i think its a control fault, from the switch possibly. I can see that there could be some sort of input from the cars ECU, but its all guess work.

I'm going over to get the car and bring it back to have a look at it in my garage and as a minimum put the Original lamps back in.

If anybody has any ideas or similar experiences, i would appreciate some feed back on this subject.

Dario

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How dark was it? Sometimes they come on when you think they don't need to and sometimes they don't come on soon enough.

Low sun an a bright day can have them coming on when not needed.

Likewise drizzly skies that are quite bright compared to the light down at road level, can have them staying off when you think they should be on.

I find the auto lights very useful but don't rely on them 100%.

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n

How dark was it? Sometimes they come on when you think they don't need to and sometimes they don't come on soon enough.

Low sun an a bright day can have them coming on when not needed.

Likewise drizzly skies that are quite bright compared to the light down at road level, can have them staying off when you think they should be on.

I find the auto lights very useful but don't rely on them 100%.

No, it was full on dark - 6:30 pm.

I was thinking it might be auto light failure, but until i get it back, i'm stuck! Bother.

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I had some cheep HIDs in the past (not on this car) and sometimes one would go off. It would need the lightswitch to be turned off and back on to get it back on again. But like you say it shouldn't happen to both.

Keep us posted.

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I had some cheep HIDs in the past (not on this car) and sometimes one would go off. It would need the lightswitch to be turned off and back on to get it back on again. But like you say it shouldn't happen to both.

Keep us posted.

They did go dim a while back and i put that down to Battery voltage issues. As a safety measure i changed out the Battery. that was about 3 months ago and there have been no issues. she does use the car infrequently though!

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Automatic headlights? Yet another option not available on the Scion iQ. The envy just keeps mounting... :(

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Like mark said also there is a light sensor right at the front of the dash board ( little dome) that shouls be kept clean and more importantly, not havee things floating around on the dash like pay and display parking tickets, handbags, resent small shopping etc. that may cover it. Usually HiD's have seperate power up converters so if your experiencing problems with both lights then it has to be a common feed. The dash dislay shoud. be showing the lights on indicator. Check the lights are on when it is displaying on the dash. The whole lighting circuit is ECU controlled. If the HID's come on when manually switched , then it has to be a sensor issue. Test the sensor by puting your hand over it But make sure you cover it completely sometimes light can pass through your skin. Best to use a thick magazine. Let us know how you get on

David

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Like mark said also there is a light sensor right at the front of the dash board ( little dome) that shouls be kept clean and more importantly, not havee things floating around on the dash like pay and display parking tickets, handbags, resent small shopping etc. that may cover it. Usually HiD's have seperate power up converters so if your experiencing problems with both lights then it has to be a common feed. The dash dislay shoud. be showing the lights on indicator. Check the lights are on when it is displaying on the dash. The whole lighting circuit is ECU controlled. If the HID's come on when manually switched , then it has to be a sensor issue. Test the sensor by puting your hand over it But make sure you cover it completely sometimes light can pass through your skin. Best to use a thick magazine. Let us know how you get on

David

Thanks David, The bugger of this, is that its internment. they came back on when she stopped and started the car a few time and the light on indicator was lit when the lights were not showing. what i can't get to the bottom of is the whether the side lights were on. I'm bringing it back today and will sit it in the garage with the lights on and engine running for as long as it takes to get the fault to re-occur. heres to a few hours of **** ache coming my way :-)

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Like mark said also there is a light sensor right at the front of the dash board ( little dome) that shouls be kept clean and more importantly, not havee things floating around on the dash like pay and display parking tickets, handbags, resent small shopping etc. that may cover it. Usually HiD's have seperate power up converters so if your experiencing problems with both lights then it has to be a common feed. The dash dislay shoud. be showing the lights on indicator. Check the lights are on when it is displaying on the dash. The whole lighting circuit is ECU controlled. If the HID's come on when manually switched , then it has to be a sensor issue. Test the sensor by puting your hand over it But make sure you cover it completely sometimes light can pass through your skin. Best to use a thick magazine. Let us know how you get on

David

David, do you know in what state the auto light sensor fails? in failure do it not conduct and there are no light? or when it fails the lights won't go out?

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Historically on the forum, no one has had the module fail. I will look on the workshop diagram but from memory the sensor is a sealed module that feeds data back to the ECU to make the decisions so not a simple LDR ( light dependent resistor) also there is hysteresis involved or the lights would be going foo and on as you passed tree's/ buildings etc. i have returned your Pm by the way

David

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Historically on the forum, no one has had the module fail. I will look on the workshop diagram but from memory the sensor is a sealed module that feeds data back to the ECU to make the decisions so not a simple LDR ( light dependent resistor) also there is hysteresis involved or the lights would be going foo and on as you passed tree's/ buildings etc. i have returned your Pm by the way

David

check your spam filter David, I responded as requested message is from dario@onboardvision.co.uk @ 7:15 this morning ;-)

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You should also check how the lights behave in manual mode to help ascertain whether the fault lies in the sensing system

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UPDATE:-

Went to pick up the car today with SHMBO and she drove back home following me. I had a signal worked out with the following car and each time the light(s) went out i singled to turn them off and than on.

over the 50 odd miles of foul weather the o/s lamp when out 10 times and the n/s lamp went out once.

I think its pretty much self explanatory and have determined that the HID units i installed these some 3 years ago are now flakey. tomorrow i will remove them and test with the original bulbs.

I'll update you guys later.

Dario

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Worth a look at the input/output connections. Maybe lucky only HR high resistance due to tarnishing. Not the best environment under the bonnet as you well know.

Good luck Dario

David

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