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Topic: fuel shut of solenoid wiring problem since making a wrong alternator connection (Read 1306 times) previous topic - next topic

Re: fuel shut of solenoid wiring problem since making a wrong alternator connection

Reply #25 –
Hya all , especially to chuck, pierce , red tractor ,you've all been most helpful , just come back from the villa , checked everything out again , there is definately no power going to small terminal , on ign solenoid , ive run a live feed direct from the battery, reasonably thick wire with a 10 amp inline fuse , and a seperate switch  connected to the small terminal on solenoid , so now when I turn ign switch on , I flick the switch you can hear the solenoid kick in , also now fuel shut down solenoid kicks in and works and all dash lights heater blowers all working etc , I've also done a test on battery booster solenoid using a light bulb connected to one side , pushed the button and lit up , so everything ok there ,  this is a job I've been meaning to do for ages , it's the winter jobs to do when it's too cold to get underneath , still I'm getting there very slowly , I put up a post a few weeks ago regarding a new parking brake chamber , I managed to get the correct part no from Les Michaels at freightliner , and managed to order one from anything truck .com , only ordered it on Wednesday , should be at my door on Monday  they were by far the cheapest , 591 USD plus 109 USD postage , time I pay the customs duty on it 25% it still works out cheaper than the quote I got from a UK distributor , I also had a quote from mill supply . Com 905usd that's before the postage , it's a haldex part but couldn't order it direct from them  had to be one of there distributors , but recommend anything truck .com to anyone , chap called Todd ever so helpful,anyway thanks to everyone that's helped me sorting out little problems mutch appreciated kev
1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo

Re: fuel shut of solenoid wiring problem since making a wrong alternator connection

Reply #26 –
The 12 VDC positive signal to close the ignition solenoid comes from the ignition switch.  So, check for 12 VDC in and 12 VDC out when the key is on.
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: fuel shut of solenoid wiring problem since making a wrong alternator connection

Reply #27 –
Quote from: red tractor –
Some coaches had a wire with a fusible link which might have been damaged by reverse polarity. You can check if there is power into the ignition switch. I think that your coach may have a Chevrolet fuse panel that would supply power to the switch. One may be labeled ignition.
this is what I've been thinking all the time right from the start that my 80 amp circuit breaker had blown , and when I checked it the other day it was OK , so I've just been up there every day this week for a couple of hrs testing everything ,, I think the problem is 99% sure the power coming out of the ING switch , because if there was no power going into the switch,then my starter motor wouldn't turnover, which it does turn over when I turn key to start position , so that is telling me there is either a problem with outlet power on switch to the small terminal on the solenoid , or it could be the wire connecting the two , or that's where the fuse could be hidden, any way for now I've solved the problem temporally,
1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo

Re: fuel shut of solenoid wiring problem since making a wrong alternator connection

Reply #28 –
, I've also done a test on battery booster solenoid using a light bulb connected to one side , pushed the button and lit up , so everything ok there

????? Maybe I'm misunderstanding your statement here but......................
There should be voltage on BOTH SIDES of the boost solenoid at all times. When the solenoid is energized it simply combines the two battery systems. If the two systems are at slightly different voltage levels then you would read a voltage across the large terminals. When the boost is "on" there should be no voltage reading across these terminals if the contacts are clean and making a good connection.

Check voltage to ground on both large terminals with boost "off" and again with boost "on" and let us know what those reading are.
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: fuel shut of solenoid wiring problem since making a wrong alternator connection

Reply #29 –
Quote from: FourTravelers –
, I've also done a test on battery booster solenoid using a light bulb connected to one side , pushed the button and lit up , so everything ok there

????? Maybe I'm misunderstanding your statement here but......................
There should be voltage on BOTH SIDES of the boost solenoid at all times. When the solenoid is energized it simply combines the two battery systems. If the two systems are at slightly different voltage levels then you would read a voltage across the large terminals. When the boost is "on" there should be no voltage reading across these terminals if the contacts are clean and making a good connection.

Check voltage to ground on both large terminals with boost "off" and again with boost "on" and let us know what those reading are.



CORRECT.  As posted earlier to verify that the boost/combine solenoid is working you need to start with the chassis and house banks at different voltages.  Measure this at the solenoid or at the batteries. 

Then turn on the boost/combine switch.  Check voltages again.  They should be EXACTLY the same since they are tied together through the boost/combine solenoid.  In essence one large battery bank now.
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: fuel shut of solenoid wiring problem since making a wrong alternator connection

Reply #30 –
Kev could use his 12V test light to check for activation signal at the small post on the front of the boost solenoid.

With dash BOOST switch OFF there should be no power (test light off) at small post.

With dash BOOST switch ON there should be 12V power (test light on) at the small post.

BUT, he still needs to do Brett's procedure to determine if the solenoid is actually closing and successfully connecting the battery banks when it is provided a activation signal.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: fuel shut of solenoid wiring problem since making a wrong alternator connection

Reply #31 –
Yup, Chuck's test will verify that the "close" signal is arriving from the dash switch.

Start with the test I posted, as it would confirm that BOTH signal is arriving and that the solenoid is functioning.

Absolutely, if voltage is not exactly the same on both banks/sides of the solenoid with boost/combine switch on it could be either a failure of the signal arriving at the solenoid or failed solenoid.  So, Chuck's test is absolutely an excellent "what do I check next".
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: fuel shut of solenoid wiring problem since making a wrong alternator connection

Reply #32 –
Yeah , I have done all those tests now , and there is no power in the small terminal which comes from the ign switch , when I connect an external live source to this small terminal , you hear the magnets click and power runs from the two big terminals , and voltage is the same on both sides , as for the battery booster , I connected a light to the non live terminal of battery booster solenoid , and the same happened when I pushed the boost switch , I heard the magnets click and the light lit up, so I'm happy with that for the time being , at least I can start. Vehicle now from key and seperate switch
1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo

Re: fuel shut of solenoid wiring problem since making a wrong alternator connection

Reply #33 –
Again, check for power IN and OUT of the ignition switch with ignition on. 
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: fuel shut of solenoid wiring problem since making a wrong alternator connection

Reply #34 –
Quote from: FourTravelers –
, I've also done a test on battery booster solenoid using a light bulb connected to one side , pushed the button and lit up , so everything ok there

????? Maybe I'm misunderstanding your statement here but......................
There should be voltage on BOTH SIDES of the boost solenoid at all times. When the solenoid is energized it simply combines the two battery systems. If the two systems are at slightly different voltage levels then you would read a voltage across the large terminals. When the boost is "on" there should be no voltage reading across these terminals if the contacts are clean and making a good connection.

Check voltage to ground on both large terminals with boost "off" and again with boost "on" and let us know what those reading are.

Just noticed one of your earlier posts on this topic , about misunderstanding me and both terminals are hot all the time , it wasn't your misunderstanding , I just forgot to mention that I disconnected the solenoid  terminal that goes to the house batteries , leaving one side hot and other side cold , then I connected light to that disconnected  solenoid terminal and then went to front and depressed the boost switch and I heard the solenoid click in and the light came on.
                  , I haven't done anymore , checking yet , been doing other things to it , got the old park brake chamber  off , new one should arrive in next couple of days , and I fitted the two rear shock absorbers, so that's just a little bit closer to getting back on road , my work is gone quiet at the mo , which I always look forward too , cause I just spend as mutch time as I can up there , but it's full on winter now over here , just had a storm come across the Atlantic from your way , probably was a hurrican originally,
1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo