Headlight issues!!

[trodgers]

Hello all, this I believe is my first official post! I bought a 2005 FS65 with a Cat motor back in september and have started converting it into an RV. First of all, thank you everyone for having such a wealth of knowledge available on this site. It has helped me immensely.

Yesterday, when bringing back the bus from painting, I realized the headlights were working at the dash had the high beams stuck "on" (blue headlight indicator). I was hoping to get some suggestions on how to start diagnosing the issue. Warning, Electrical is not my strong suit.

I believe its a head light relay or the turn signal/highbeam switch. When I hit the high beam switch, there is no "click" from the fuse box. this tells me something is capoot.

I know it could be a ground or short somewhere. I am dreading tracking it down. I dont have a wiring diagram for the bus . I am also moving out of state at he end of month and although I can drive the bus without headlights, I would REALLY like for everything to be working properly. Any tips/tricks, would be greatly appreciated.

I live in detroit and would gladly hand out food/beer for anyone that could educate me more on this thing.

Thanks all!

[EastCoastCB]

prob has daytime running lights. Maybe the module is malfunctioning. I've removed one for that reason before. Brights stayed on ALL the time till I removed that DRL module.

[trodgers]

Day time running light module? Do you know where this might be located or what it looks like? Once I find it, I can pull the PN off it and see how to replace it.

Thank you for the advice

[banman]

Is this a Thomas body on a fs65?
Don't know how much would change from my 2002...
I have a single headlight (each side) with high & low filaments in each light.
Are yours one or two per/side?

First off, have you confirmed the headlights are actually on highbeam and not just the dash panel indicator bulb on?

My lowbeams (DRL) come on (if the ignition is on) when the parking brake is released.

Not at my bus at the moment but I believe the headlight circuit breakers are on the fuse panel to the right of the steering wheel. You can try removing the HB breaker and see if the LB function is restored.

[EastCoastCB]

Originally Posted by trodgers

Day time running light module? Do you know where this might be located or what it looks like? Once I find it, I can pull the PN off it and see how to replace it.

Thank you for the advice

I found mine by feeling around with my hand. It was warm. Tested with a multimeter to make sure and it was getting power on both sided all the time if I'm remembering right. Looked like a small aluminum car stereo amp I think- about 4"x6" maybe. I used google images to identify it at the time. That was a 2003 Thomas.

Could be a few things, though. I suck at electricity stuff.

[trodgers]

Banman- Yes its a thomas on a FS chasis. I have 1 head light on each side. Im not at the bus right now but I believe on the interior dash fuse box ther is a right and left fuse. I dont remember seeing a fuse for higha nd a fuse for low. I did see the relays though. I have not confirmed the high beams are off and the indicator light is just on. The indicator light does come on when the rocker light switch changes position along with the dash lights. I can post a picture though tomorrow.

East CoastCB- Were you feeling under the dash, off by the interior fuse panel, or....

I really do appreciate the help.

[EastCoastCB]

Originally Posted by trodgers

Banman- Yes its a thomas on a FS chasis. I have 1 head light on each side. Im not at the bus right now but I believe on the interior dash fuse box ther is a right and left fuse. I dont remember seeing a fuse for higha nd a fuse for low. I did see the relays though. I have not confirmed the high beams are off and the indicator light is just on. The indicator light does come on when the rocker light switch changes position along with the dash lights. I can post a picture though tomorrow.

East CoastCB- Were you feeling under the dash, off by the interior fuse panel, or....

I really do appreciate the help.

On the bus I had the issues with there was an electrical panel outside under the driver's window.

[trodgers]

I am still scratching my head on where the DRL module is. Below are attached photos of the interior fuse box, and the exterior along with the panel schematic. I have also attached the pdf from thomas on the electrical schematic.

Another question, what is a "genuine bus scan" from RTI? It buzzes after shut down and I am curious why. This bus also has something from Webasto. I dont know what it is either.

I tried to replace the turn switch and the head light relays, no luck. one odd thing I found was that the turn signal had an open connection. One of the prongs didnt have an associated wire. Wasnt sure if this was common... Below are some pictures, please let me know if anyone knows about the webasto, bus scan, or the DRL module. Thanks all!













__stnaftbbo002.us605.corpintra.net_h096_jsmolde_Data_My Documents_1XXXXXXXXXX_1FRIDAY_1_D06-4604.pdf

[trodgers]

__stnaftbbo002.us605.corpintra.net_h096_jsmolde_Data_My Documents_1XXXXXXXXXX_1FRIDAY_1_D06-4584.pdf

It for some reason wouldnt fit alll on one post.

[banman]

My bus does not have the exterior compartment -- different setup...

The Webasto and "genuine bus scan" are add-ons used by the school district that had your bus.

Removing them can be difficult -- be sure to understand the wiring and purpose before dissecting...

[BlackJohn]

I read all this and still am not sure if you have any light from either headlight.
Do you or don't you, check when it is dark, going from low beam to hi beam.


The drawing helps but doesn't give location of the DRL, but the DRL is wired to the blue hi beam indicator in your dash panel.


A wire from the DRL also goes to the signal light switch it appears for dimming purposes. It is normally open and closes when you pull back I presume. This might be what you saw with one wire as it only switches the grounding of that selection.


You have a relay for each headlight, are they working? You have circled some that are not to do with headlights.

Headlight relays will be warm to the touch with switch on for headlight operation.



If you have a multimeter, you can pull the headlight relays and check for 12v power to a good ground. You need power from the battery and power for the coil and if the relay is good, you get lights when the parking brake is released as someone above mentioned.


The DRL might be under the dash, driver side or could be external but not in the control panel you show, likely firewall or near it.


That is enough for now, other items can wait or someone else chime in.


John