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Re: Continuing electrical issues (12 volt side)

Hey Pierce..I've got starting problems in Oregon...start batteries show 13 volts but only have 8.5 at the big relay under the dash?
1994 U300

Re: Re: Continuing electrical issues (12 volt side)

Reply #1 –
David,

Sounds like a loose or corroded connection or bad wire.  Check first at battery end.
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: Re: Continuing electrical issues (12 volt side)

Reply #2 –
Quote from: kb0zke –
  I also need to get some sort of label maker so I can mark all the red lines. Now, which lump of black, greasy crud is the ground?

I have to thank one of the POs of our coach for having a label maker!  ^.^d
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: Re: Continuing electrical issues (12 volt side)

Reply #3 –
So..the big cable coming into the dash start battery continuous duty relay drops virtually all voltage when you turn the key on. I assume (there's that bad word) that I have a bad connection on the other end of that big number 4 guage wire.? Where does the wire feed from?
1994 U300

Re: Re: Continuing electrical issues (12 volt side)

Reply #4 –
Quote from: daviddeann –
Where does the wire feed from?
Daviddeann,

It is helpful if you identify your coach model and year - wiring/component location can be quite different in various models.

On my coach ('93 U280) the 4 gauge red wire feeding the ignition solenoid originates at a large round 90 amp circuit breaker located on the main 12 volt circuit breaker board in my center storage bay.  It is covered with a white fiberglass cover.  When you remove the cover (CAREFULLY - some connections under this cover are always HOT), you will see (among other things) 3 big round circuit breakers.  The one on the left (on my coach) supplies power to ignition solenoid.  The feed INTO this circuit breaker comes directly off the ENGINE START post on the isolator, so it should read the same voltage as the start battery bank.
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"