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Topic: Headlight control relay (Read 746 times) previous topic - next topic

Headlight control relay

Does anyone know were the headlight control relay is?
 I interminably have is fail off while switching from high to low beam. Bit unnerving in the dark.  Suspect the contacts are burnt.
Thanks Scott

Re: Headlight control relay

Reply #1 –
I would think they would be behind the dash panel next to the entry door above the battery disconnect. That is where the blinker relay is, anyways.
1999 U320 WTFE #5586
2014 Subaru Forester 6sp
4000 watts of solar
650 aH @ 24v

Re: Headlight control relay

Reply #2 –
Your coach should have 2 relays one for just headlights and the 2nd for high beam.  They are hid behind the removable kick panel in front of the passenger's seat. On our coach they are on the side of the breaker panel running vertical. Ours are the bottom 2 relays high beam is the bottom one.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Headlight control relay

Reply #3 –
Isn't there an auto reset circuit breaker in the circuit also?
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Headlight control relay

Reply #4 –
Quote from: craneman –
Isn't there an auto reset circuit breaker in the circuit also?

Yes actually there are 2 one for regular lights and a second for high beam. Seems like the regular headlights breaker is in the mid 30s and the high beam is in the single digit breakers.  I will have to pull a print to be sure.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Headlight control relay

Reply #5 –
Quote from: dsd –
Does anyone know were the headlight control relay is?
 I interminably have is fail off while switching from high to low beam. Bit unnerving in the dark.  Suspect the contacts are burnt.
Thanks Scott
Scott, the smart wheel circuit board has a failure point.  I had this problem, though unfortunately I did not document, or can I even recall my solution unfortunately.  The high amp draw heats and melts the solder on the board. 

Headlights


The problem is well documented on other brand forums from what I recall, and there is an outfit in Oregon that sells a connector that helps solve the issue.  Sorry on the bad memory, but I suspect you issue is rooted in the  Smart Wheel circuit board.

Here is the plug that seemed to be a problem child over the years:

Replacement J12 Plug - Northwest RV Supply
2000 U320 4010

Re: Headlight control relay

Reply #6 –
I think this is the controller:

VIP Smartwheel Control Module SM210 - Northwest RV Supply

And the troubleshooting guide:

https://www.nwrvsupply.com/wp-content/uploads/2022/08/TROUBLESHOOT-SM210.pdf

My issue was with the J12 connection, again, don't recall the solution.  Based on your other problems you've solved on your coach, this will be a walk in the park and opportunity to upgrade.  I really want to upgrade my headlights with relay based power, as our coaches come from the factory, all headlight power goes through the switch and this smartwheel controller.  Lots of voltage drop. 
2000 U320 4010

Re: Headlight control relay

Reply #7 –
Quote from: evantwheeler –
I think this is the controller:

VIP Smartwheel Control Module SM210 - Northwest RV Supply

And the troubleshooting guide:

https://www.nwrvsupply.com/wp-content/uploads/2022/08/TROUBLESHOOT-SM210.pdf

My issue was with the J12 connection, again, don't recall the solution.  Based on your other problems you've solved on your coach, this will be a walk in the park and opportunity to upgrade.  I really want to upgrade my headlights with relay based power, as our coaches come from the factory, all headlight power goes through the switch and this smartwheel controller.  Lots of voltage drop.

So I really think by its behavior it's in this area, but the information you provided will help to troubleshoot. Thank you very much. $400 for a replacement unit may be enough incentive to update the wheel if it comes to that.

Re: Headlight control relay

Reply #8 –
Quote from: Pamela & Mike –
Your coach should have 2 relays one for just headlights and the 2nd for high beam.  They are hid behind the removable kick panel in front of the passenger's seat. On our coach they are on the side of the breaker panel running vertical. Ours are the bottom 2 relays high beam is the bottom one.

Mike
I dont think it is a power supply problem, you flash the high/low beam switch a couple times and it will fire back up and work well. I had checked the controller wire prior and they all looked good. Easy to check the relays once I have my hand on them. While im digging in there I'll double check the controller also. Thanks for the info

Re: Headlight control relay

Reply #9 –
So last week I found and replaced the high beam headlight relay. Little Bosch relay. Replacement worked perfect after. So being curious I stressed the relay case till the top popped off. Visually looked great. Wasn't expecting that. VOM indicated .8 ohm resistance across contact. Literally just blew across contact and it worked fine after that. Tossed it in the trash. Drove down to Laughlin this past weekend and it worked normal.

Re: Headlight control relay

Reply #10 –
Saga continues. Headlights have several times gone off or on with use of the ICC switch. Happens on both Hi and Low beam position. Got into the wiring diagram and the only thing that shares power to Hi and low is the J12/P12 connector on the smart wheel controller. Inspected wires on J12 plug and others as good. Finally was able to see a power interruption on J12 wire 1 and 2. They are the switched light power for headlights and running lights are J12 wire 3 and four. This isolated to relay 512ND12-W1 in that position as pointed out in photo inside controller. Ordered a replacement solder in relay. Hopefully this will resolve my issue before I have to send it out for repair or replacement of controller. Installed an emergency override switch to dedicate power without interruption across relay contact 1 and 2 on J12.