Headlight ballast controller issues

Supertrooper · Wednesday at 10:25 PM

I have just had the near side dipped beam bulb replaced on my 2007 Lexus 400h but it won’t light up. So I have been advised it’s the ballast controller which I understand is attached to the back of the headlight cluster itself. 2 Questions.
1) Does the ballast controller affect only the dipped beam?

2) I if I need to remove the headlight cluster, can you give me a step by step guide to do so, please, or direct me to a post or video?

thank you in advance

Gordon

katabrontes · 2024-11-21T08:45:23Z

Is the bulb reversible, ie can it be plugged in after rotating 180 degrees. It could be a polarity issue.

ColinBarber · 2024-11-21T13:56:02Z

15 hours ago, Supertrooper said:

1) Does the ballast controller affect only the dipped beam?

Yes, HID is only for dipped. High beam uses a conventional halogen bulb.

Supertrooper · 2024-11-21T17:12:34Z

8 hours ago, katabrontes said:

Is the bulb reversible, ie can it be plugged in after rotating 180 degrees. It could be a polarity issue.

Thanks for responding, Michael. I have no idea. I had Halfords fit it. When the replacement failed it was them that suggesated it was the ballast.

Supertrooper · 2024-11-21T17:38:33Z

3 hours ago, ColinBarber said:

Yes, HID is only for dipped. High beam uses a conventional halogen bulb.

Hi Colin. Thanks for you input.

The saga continues. I took the car to the best garage to me, an their immediate question was, "Is there any water in the headlight assembly? Because, if there is, over time, it will go down into where the ballast is and corrode everything"

We all looked and, sure enough, there was condensation, although, to be fair we had a small amount of hail when Halfords were fitting the HID bulb last night. Some moisture may have got in then but, may be not.

None-the-less, the verdict was to replace the whole assembly. The problem with that is, new, their price puts them beyond me and, pre-owned, how do I know they are not leaking.

So, I have been considering fitting LEDs and by-passing the Ballast completely, as well as forgetting about the self levelling.

Any thoughts?

Cheers,
Gordon

Jaystar77 · 2024-11-21T18:27:05Z

Hi Gordon, not sure if it's of any help but I've the remains of a RX350 passenger side headlamp here somewhere. Was in a smash a few years back and kept whatever looked useful. Headlamp was mangled but the innards looked fine. Not 100% sure on compatibility with RX400h but free to a good home if it digs you out of a hole.

ConorW · 2024-11-21T18:55:15Z

1 hour ago, Supertrooper said:

Hi Colin. Thanks for you input.

The saga continues. I took the car to the best garage to me, an their immediate question was, "Is there any water in the headlight assembly? Because, if there is, over time, it will go down into where the ballast is and corrode everything"

We all looked and, sure enough, there was condensation, although, to be fair we had a small amount of hail when Halfords were fitting the HID bulb last night. Some moisture may have got in then but, may be not.

None-the-less, the verdict was to replace the whole assembly. The problem with that is, new, their price puts them beyond me and, pre-owned, how do I know they are not leaking.

So, I have been considering fitting LEDs and by-passing the Ballast completely, as well as forgetting about the self levelling.

Any thoughts?

Cheers,
Gordon

This happens to me … the ballast actually burned out and the bulb fried in its socket.

would love to replace with LEDs but haven’t got a clue which ones would be suitable.

ColinBarber · 2024-11-21T20:47:51Z

3 hours ago, Supertrooper said:

So, I have been considering fitting LEDs and by-passing the Ballast completely, as well as forgetting about the self levelling.

It could be an MOT failure if detected.

katabrontes · 2024-11-22T09:50:00Z

I have seen reports about MoT failure if bulbs are replaced. I have fitted HID main beam bulbs to my 2006 RX350 about 8 years ago and recently replaced them with, much better, LEDs. Also replaced reversing lights with LEDs. Never had a problem with MoT.

Supertrooper · 2024-11-22T11:45:56Z

Right, this is what I'm thinking of doing. The LEDs for the Lexus RX400h have their own driver built in to the base of the bulb, so they don't need the balast unit which I understand provides the driver for the Xenon light. So I'm investigating accessing the power lead going into the the Balast and connecting leads from that direct to the LED each side. That keeps the self-levelling operational, whilst the ballast controller works. But if the ballast controller fails, no problem, I still have all lights.

I have had many estate cars that had manual levelling and never needed to use it. So I don't really expect to be needing the self levelling in my Lexus.

Any thoughts would be welcome. 🙂

Gordon

Supertrooper · 2024-11-22T11:50:30Z

17 hours ago, Jaystar77 said:

Hi Gordon, not sure if it's of any help but I've the remains of a RX350 passenger side headlamp here somewhere. Was in a smash a few years back and kept whatever looked useful. Headlamp was mangled but the innards looked fine. Not 100% sure on compatibility with RX400h but free to a good home if it digs you out of a hole.

Hi Jay, that's very kind of you. Looks like the bottom picture has the ballast, its container and wiring/connectors. I may find a good home for those. How can we best proceed?

Gordon

Herbie · 2024-11-22T12:03:51Z

11 minutes ago, Supertrooper said:

Right, this is what I'm thinking of doing. The LEDs for the Lexus RX400h have their own driver built in to the base of the bulb, so they don't need the balast unit which I understand provides the driver for the Xenon light. So I'm investigating accessing the power lead going into the the Balast and connecting leads from that direct to the LED each side. That keeps the self-levelling operational, whilst the ballast controller works. But if the ballast controller fails, no problem, I still have all lights.

Just be careful when messing about with the ballast. The HID lamps have quite a specific requirement that the ballast provides.

HID lamps are basically arc lights. It takes in the region of 20-25kV to strike the arc and around 80V to sustain it, so wear insulated gloves and wait at least 10 minutes after switching off before you go anywhere near it.

Supertrooper · 2024-11-22T14:18:50Z

4 hours ago, katabrontes said:

I have seen reports about MoT failure if bulbs are replaced. I have fitted HID main beam bulbs to my 2006 RX350 about 8 years ago and recently replaced them with, much better, LEDs. Also replaced reversing lights with LEDs. Never had a problem with MoT.

Hi Michael, that's good news! Can you tell me what LED brand and number you used, please?

Cheers,

Gordon

Supertrooper · 2024-11-22T14:33:43Z

2 hours ago, Herbie said:

Just be careful when messing about with the ballast. The HID lamps have quite a specific requirement that the ballast provides.

HID lamps are basically arc lights. It takes in the region of 20-25kV to strike the arc and around 80V to sustain it, so wear insulated gloves and wait at least 10 minutes after switching off before you go anywhere near it.

Hi Herbs,
That's an excellent point. I trained as an auto and agric engineer many decades ago. I am a bit too long in the tooth to be able to be under bonnets or under cars, now. So I am hoping to get advice from you and others as to whether my plan is good as well as what could go wrong, (including electrocutiion). Then taking that knowledge to a good local garage and explaining, to them, exactly what I want done and, what to be careful of.

So your input is invaluable,

Thank you,

Gordon