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Topic: Boost switch Solenoid Location?? (Read 1877 times) previous topic - next topic

Boost switch Solenoid Location??

My Boost switch has never worked and I have never needed it, I would like to fix it just in case I need it someday...So I have a 1996 U270 and my question is where is the solenoid located so I can test, can anyone chime in with this info?? Thanks
1996 U270 36'

Re: Boost switch Solenoid Location??

Reply #1
On my last three coaches it is located near the isolator. It is a silver squat metal device with two flanges for the screws to hold it to the back of where the bed or the closet entry is.  It has a couple lugs with bigger wires and a smaller one in the middle I think. I will have to look at it to be sure but I know what it looks like when I see it.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: Boost switch Solenoid Location??

Reply #2
Thanks..I start by looking around the bed area.. I know I have alot of stuff located under the foot of the bed like all my breakers/switch box
1996 U270 36'

Re: Boost switch Solenoid Location??

Reply #3
My Boost switch has never worked and I have never needed it, I would like to fix it just in case I need it someday...So I have a 1996 U270 and my question is where is the solenoid located so I can test, can anyone chime in with this info?? Thanks

Here is what mine looks like. Located under the bed next to isolator.

How do you know it is not working?
Mine has a red light on the rocker switch that sometimes needs replacing but the boost switch is still working.
The selected media item is not currently available.Barry BEAM #16014
2003 U320 40' AGDS
Beamalarm, Foretravel technical help and specifications
"Whatever the mind can conceive and believe, it can achieve"

Re: Boost switch Solenoid Location??

Reply #4
Easy test of boost solenoid, Have someone in drivers seat turn it on and off while you listen near switch in rear.  You should hear it click. Also use a meter across lugs, should get no voltage reading until switch is engaged and then you should get battery voltage. Can also use 12v test light to test. If still no voltage across lugs, use test light on small wire lug and turn switch on and off, if no voltage here fault will be either at switch or a broken wire.
Gary B

Re: Boost switch Solenoid Location??

Reply #5
Barry, No light at switch, on or off, and no diff in dash voltage gage when switch is activated...
Gary,, I'll try the noise test tomorrow. If I can just located the solenoid I have a meter to test.. Thanks for the help
1996 U270 36'

Re: Boost switch Solenoid Location??

Reply #6
If you have a voltmeter, go to the boost solenoid:

Check voltage at each of the two LARGE lugs with boost switch OFF.  They should be different and reflect the voltage of the two battery banks (one chassis, the other house). There should be no voltage to the small signal wire. If two small terminals/wires one will be ground, the other the signal wire from the boost switch.

Turn on the boost switch.  If the wiring, switch, etc are operating properly, the small sense wire should now have 12 VDC to it AND as suggested, you should hear the "CLICK" as the solenoid closes.  And, voltage at the two large terminals will be the same, since the job of the solenoid is to connect the two battery banks.

If, with the boost switch ON, there is not 12 VDC positive to the small signal wire, something "upstream" of the solenoid is at fault.  Easy to test the solenoid in this case.  With the positive signal wire off it's small terminal, use a small jumper wire (will carry less than one amp) between either large lug and the positive signal lug.  You should now here the solenoid click in and should read the same voltage on both large lugs.

Brett
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Boost switch Solenoid Location??

Reply #7
Makes sense.. Sounds like the way I used to jump start this old tractor my Grandpa used to have. Now if I can just find the solenoid..The picture Berry posted looks like something I have seen bolted to my frame behind the driver side rear tire...will look tomorrow
1996 U270 36'

Re: Boost switch Solenoid Location??

Reply #8
This pretty much the way ours looks on a 99' U270... Except that Barry's engine compartment insulation looks much better than ours! Basically, just stand at the end of the bed, open the engine cover and look down into the engine bay and it is right in front of you on our coach.
Don

 
Here is what mine looks like. Located under the bed next to isolator.

How do you know it is not working?
Mine has a red light on the rocker switch that sometimes needs replacing but the boost switch is still working.
The selected media item is not currently available.
Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Boost switch Solenoid Location??

Reply #9
Should be petty easy to identify.  Will only be one solenoid in the coach that has both large lugs HOT but at different voltages.

Brett
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Boost switch Solenoid Location??

Reply #10
mine is located above the starting batteries, next to isolator.
rear compartment curb side.

Re: Boost switch Solenoid Location??

Reply #11
An easier way to test a solenoid is to plug in to 120 ac. The voltage of the house batteries should read around 13.2 volts. Measure the start battery, it should be around 12.6. Switch on the boost and measure the start battery again. If the solenoid is good, the voltage should climb to match the house batteries.
1994 U280, Build 4490
Deming, NM.

Re: Boost switch Solenoid Location??

Reply #12
96u270
Here is where mine is on another 96 U270...inside the door behind drive tires, driver side...the solenoid on the right, the one with the heavy cables.
Ralph
96 U270

Re: Boost switch Solenoid Location??

Reply #13
Here is what mine looks like. Located under the bed next to isolator.

How do you know it is not working?
Mine has a red light on the rocker switch that sometimes needs replacing but the boost switch is still working.
             
Quote
So Barry, what is the process to change out the light? My light is out but I know the boost is working.
Here is how I do it.
Rocker Switch Bulb Replacement
Dean & Deirdre

2012 Arctic Fox 22GQ
Was 2003 U270



Re: Boost switch Solenoid Location??

Reply #16
Thanks for all the help.. Thanks Ralph for the picture, that's got to be where it's hiding... And I'm going to check the light 2
1996 U270 36'

Re: Boost switch Solenoid Location??

Reply #17
Well after looking at Ralph's picture again, I see two solenoids that look alike.. Is it the one on the left or right???
1996 U270 36'

Re: Boost switch Solenoid Location??

Reply #18
Well after looking at Ralph's picture again, I see two solenoids that look alike.. Is it the one on the left or right???

The one on the right with the big cables. Check the previous posts on this topic for the newest Cole-Hersee model number or consider going to a solid state solenoid. 

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Boost switch Solenoid Location??

Reply #19
I have just replaced the boost solenoid on my GV.  I had DW listen and she reported not only a click when I switched it on but also a hum from the coil holding the contacts closed.  I had to replace the single wire original unit with a two wire Cole Hersee 24213-BX, according to the box it came in.
John Cooper
'91 GV 36'
Oshkosh chassis
Cat 3208T 300HP

Re: Boost switch Solenoid Location??

Reply #20
Update...I replaced the light in the rocker switch and bingo the light works in the on position.
Next I parked next to a wall and opened the driver window and I could hear the thing ''Click'' when I turned the switch on and off.Now I used my voltmeter and with it on one side I got 12 volts and the other side I only saw 6 to 7 volts so I'm thinking the solenoid is junk..

1996 U270 36'

Re: Boost switch Solenoid Location??

Reply #21
If you truly measured 6-7 VDC on one of the large lugs of the boost solenoid, you either have dead batteries on that bank OR bad connection somewhere.

Again, each large lug should have EXACTLY the same voltage measured at the battery bank it is connected to.

Brett
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Boost switch Solenoid Location??

Reply #22
OK,,Tomorrow I will pull and clean connections
1996 U270 36'

Re: Boost switch Solenoid Location??

Reply #23
And I did check all batteries and all are good
1996 U270 36'

Re: Boost switch Solenoid Location??

Reply #24
As Brett said, with that big of a voltage difference, you got the have a bad connection or cable. A little hint unhook the cable with the low voltage at the solenoid then check the voltage, just keep going back on that cable until you find the problem connection/cable. More that likely you will find the problem where the terminals are crimped on the cables, they can look good but be corroded on the inside. On coaches of older vintage these kind of problems are common given the age of the battery cables. Be careful working with metal tools around those heavy cables they carry a lot of amps.  Happy hunting.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country