First off hey everyone I need some help here I have always had f150 for a truck just my first time on a forum.

My question? I recently purchased an hid kit and installed. It worked great for a month, until one rainy day my headlight went out on the passage side. After a lil research I found water in the stock wiring plug to the passenger headlight. I blew it out with air and dried it real good and reconnected my headlight and still nothing so I ordered a new HID ballast and new bulb and nothing again with the new. so I checked the low beam fuses and they are fine. finally I checked DC volts to the plug and I get 4.8 volts from the plug low beam side only. it should be 12. my high beam works great! 12 volts, just not the low beam. I dug a little more and am discovering it may be the lighting control module that shorted out! I did try to reset the module by unplugging the batt for ten minutes and still no luck. any ideas guys I'm out of them and really hope it's not the module I believe it is now intergraded in the BCM. body control module.

Thoughts???
Thanks in advance!

 

Hi & welcome!

I think you may have discovered why a LOT of folks here say those cheap chinglish POS PnP HID kits are bad news.

Job #1 - List details of truck - model year, has DRL's, etc.

First principles: if you reconnect ALL of the wiring back to stock, do both yer factory Halogen headlights - low & highbeams work as expected?

If the answer is 'Yes', it's not the truck - it's the kit.

If 'No' - more vehicle info is needed.

BTW - you ARE at least using a relay harness for the HID kit, right?

MGD

 

2010 f150 fx2 2wd. nothing from stock halogens. The kit came with a ballast and the wire harness was connected to the light to plug into the ballast and to the stock harness.

 

OK. Explain "nothing from stock halogens" = same as before only one lowbeam is inop? You need to be concise in yer descriptions.

IF a completely stock OEM halogen config isn't working, there may likely be an internal problem in the SJB ( 2009+ trucks all have this integrated lighting management & control system ).

Looks like Dealer visit time - after you have positively checked & confirmed all related fuses with a meter ( utilizing the test pins on the back of the fuses ).

Note - remember to use dielectric grease on all connectors to seal out moisture.

Foinall - I think you need to chitcan that POS PnP can' o' worms.

Refer to the site I referenced for Quality HID retrofit components & systems.

MGD

 

Sorry yes I have the same exact issue with the low beam not working. and high beam does work just fine. I tested voltage again to the same conclusion only getting 4.8 volts from the low beam. I don't understand why the fuse didn't go out to protect the circuit from damaging the lighting module? is this module something I can purchase or is it integrated in the BCM?

 

I will have to load each connection with grease when I get this solved.

 

Hi.

It's here: https://www.f150online.com/forums/me...ior-lamps.html (courtesy of Steve Scully)

Wait - are you measuring that voltage without a load? You can't do that on these trucks - the SJB will think the bulb is out and turn off the output.

Try this: plug into a Known Good H13 halogen bulb, turn on the heads and try again - backprobing the light socket. What is the voltage?

Could also be a bad socket, or wiring fault which th DJB is reacting to and turning off the juice.

High-impedance DVM's will read falsely on unloaded outputs sometimes, picking up stray induced voltage.

The SJB is well-protected - it's microprocessor-controlled and uses load sensing, with FET outputs.

MGD

 

I have checked with a load to the light and that is what I am getting when I check it with the stock bulb. I looked at the socket and all looks good as well as the wiring. What are the odds this all goes out when the connectors are full of water and having a bad wire, prob slim. it's a well maintained 2010. weekend driver. I like the response MGD I gave me a little more light at the end of the tunnel, I just looked into all of that. So what you are saying is it is unlikely its the lighting control module?

 

Hi.

Wellsir, you are doing a purty good job eliminating possible causes.

Apart from the water issue, which could still be the cause - a constant fault like a partial ground path due to entrapped moisture somewhere may well be enough to cause the SJB to turn off that specific circuit.

The only real way to confirm this is to isolate that portion of the harness check it for both good continuity and any paths to ground.

IF that checks out, then the only thing left is the SJB. I suspect the dealer has method to diagnose a SJB electronically to confirm internal operation.

MGD