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rvoregon's avatar
rvoregon
Explorer
Sep 16, 2015

Aux Start Problem

I've got an electric problem in my RV and will try and explain as best as I can.

I have a 29 foot, 1998 Minnie Winnebago (Ford Triton V10)

I've had my RV for 1 year and the Camdec Solenoid (97226) was never working, so I finally got around to replacing it:
https://goo.gl/photos/eWBAMsbHYfDnwjNYA

However, as it is was originally wired from the Aux Start switch (Carlingswitch V5D1), when the switch is not pressed, the solenoid is getting 12 volts and is in the on position. When I hit the switch, it turns to the off position.

After removing the wiring from the panel, here are the 3 switch wiring options I have tried:

Options A - original (switch is working as described above)
https://goo.gl/photos/YQo46zC2tZP5M9dX8

Option B - reversed connection (switch works OK to turn on, but the solenoid stays in the on position, even after the switch is released)
https://goo.gl/photos/qGYkyZQXC4zkAkh9A

Option C - modified reversed connection (only using 2 of the switch connector - works great)
https://goo.gl/photos/Q7EGaK2W12Pa3uay8

So for options B and C, the solenoid is controlled by a switch connecting terminals 2 and 3. For option B, terminal 1 is also used and for option C, terminal 1 is not used.

After playing around with this for several hours last night, I was looking for a little help.

- Andy
Class C

4 Replies

  • CA_Traveler's avatar
    CA_Traveler
    Explorer III
    Sep 27, 2015
    No not correct. The basic design is for automatic charging of the house batteries when driving. There can be a delay before the charging starts from the electronics if any or immediate when enabled from the ignition.

    Why would it be designed otherwise? If it's manual as you're describing then first confirm from the mfg that it's working as designed and then change it, IMHO.

    The emergency start (or whatever it's called for your rig) is designed to start the engine when the chassis battery doesn't by itself for whatever reason.
  • rvoregon's avatar
    rvoregon
    Explorer
    Sep 27, 2015
    Pretty much what DrewE indicated (I was overthinking it).

    Normally, the solenoid is not powered and thus the batteries are not connected. Throwing the momentary toggle switch sends 12 V to the solenoid, which links the batteries.

    And here is where I was getting messed up. If I turn the ignition one click (radio works, but doesn't start the engine), the solenoid is powered, thus linking the batteries. However, when I turn it one more click (starting the engine), the power to the solenoid turns off. So generally, when the engine is on, the solenoid is off. However, if I then hit the switch when the engine is on, the solenoid turns on and stays on (presumably so that the house battery can charge when I am driving).

    So if I am correct, when driving, I can chose to either have the batteries linked or not.

    Pretty sure this is right. Maybe. I think.
  • CA_Traveler's avatar
    CA_Traveler
    Explorer III
    Sep 16, 2015
    Maybe the wiring when you got the rig had been changed. If it's a lighted switch then the third wire could be for the light.
  • DrewE's avatar
    DrewE
    Explorer II
    Sep 16, 2015
    I think the first step is to determine what the internal wiring of the switch is. My guess is that it's a single pole double throw switch (presumably momentary), so there's a common connection, a normally open connection, and a normally closed connection.

    If that's the case, I would guess that the common should be wired to the solenoid control wire. The normally open is connected to +12V, probably from the house battery. The normally closed one is probably connected to a switched lead in the chassis somewhere so that the solenoid closes while the engine is running and permits the house batteries to be charged by the engine alternator. It may actually be a little more sophisticated circuitry than just a switched-by-the-ignition wire, but the general idea is similar.

    If this is indeed the intended setup, then when you have the engine running, or perhaps just the ignition in the on position, the relay should normally be operating to connect the two batteries together. If the ignition is off, the relay should only operate when the aux start button is pressed. Staying closed in this case implies that the switched chassis lead is not wired properly or whatever is controlling it is not working properly.

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