Auxiliary start switch query

[RetiredGuy]

The switch on the dash of my Land Yacht acts like a conventional rocker switch, meaning it has no spring function. My understanding about auxiliary start switches is that they have to be held down to operate, which will prevent you from running your starting battery down while parked.

Can anyone advise me if my switch is operating correctly? Thanks.

[DaveFL]

My 2000 has a momentary rocker switch "on while depressed"
If yours stays on, PO might have used it while parked plugged in and that way charger would charge both.
I am going to add an engine battery disconnect so that those small built in items discharging battery on long term sitting won't happen.

[gloran]

on my 93LY the purpose of the auxiliary rocker switch is, if your starting battery has become run down you can engage this switch while turning the key and it draws power from your coach batteries to assist in starting the engine. It is a momentary or spring type rocker switch, it has to be held in to operate additional batteries help.

[batwingz]

No, Your switch is broken. The switch is spring loaded "hold to energize" a solenoid that ties the coach and starter batteries together. I recently replaced my switch was was doing the same thing yours is. Once the switch was replaced, I found out that the solenoid also needed replacing (the failed switch burnt the contacts on the solenoid) It works fine now. In the process of locating the solenoid, I also saw a product called a Ultra Trik-L-Start. I installed this easily at the solenoid connections.

Fixed a lot of issues.

[fabu007]

gotta try this as the battery nis fried again and there is no spring action... also refrig stopped workin while plugged in unless aux by key position...

[RetiredGuy]

To all who replied to my query, sorry for the late response but I am getting lazy in my retirement....

Batwingz, thanks for the tips and the info on the Trik-L-Start, I have already replaced the solenoid on my coach but left the wire to the switch disconnected. The solenoid is something readily available from a decent auto parts store but the nearest A/S dealership is an hour's drive away.

I am really in no hurry to get a replacement switch. Seems to me using the auxiliary start switch is a very rare event anyway. Doesn't the isolator prevent running the coach battery down, assuming the switch and solenoid are working properly? I can easily use the coach batteries to boost the starting battery by using jumper cables, or by using our toad and the cables, or by using the genset to power a battery charger with a boost starting feature.

Makes me wonder if the switch/solenoid problem is related to the mishap the prior owner had, he forgot to unplug the shore power cable from the campground plug prior to driving away and tore it out of the chassis. When I purchased the coach one of the first things I did was repair the cable, and after doing that I found the coach batteries would not charge from shore power. The OEM converter, a 50 amp Powersource from Todd Engineering, would not put out any voltage so I replaced it. Replacing the converter was somewhat of a headache, after removing the passenger seat and lower dash panel, I found the particleboard dash panel had been badly water soaked and ruined. I made a new one out of 3/4 plywood and got replacement carpet to cover it from under the shower stall. Since the OEM converter was mounted vertically on the kick panel and hard to access, I decided to mount the new converter, a 60 amp Intellipower 9200D, at an angle under the heater fan motor. Two steel bars were fastened to the top of the heater core box and the floor, and the connections to the converter are MUCH easier to access than the OEM model was.

Would it have been possible for the drive-off-while-plugged-in to ruin the OEM converter and solenoid/switch?

[lesvoyageurs]

We recently purchased a 1995 LandYacht Wide Body Diesel. There is an Auxiliary Battery switch on the dash and also one by the door. We thought the purpose of the switch on the dash was to connect the coach batteries (4 located in the front) with the engine battery (1) located in the rear if you had problems starting the engine. We actually saw a dealer start a 1990 LandYacht using the Auxiliary Switch on the dashboard for this very reason. However, our 1995's engine battery was low, and we tried the Auxiliary Switch to start the coach and it didn't work. We have the coach at an Airstream restoration shop now and they said they do not believe that the Auxiliary switch in our coach is designed to connect the batteries. Does anyone know if Airstream changed the function of the switch between 1990 and 1995? And what is the function of the Auxiliary Battery switch near the door? Thanks so much for any help you can give. We are newbies!

[batwingz]

I also have your exact model. You are correct in assuming that your coach has an auxiliary start feature that bridged both sets of batteries for emergency starting. The switch near the door is a master cutoff to kill power to the coach from the house batteries. Usually used when you store the unit for an extended time.

Open your engine maintenance door and on the right side you will see a large silver relay. This is the auxiliary start relay that is connected when you push the button on the dash. These relays go bad and are relatively inexpensive. You will see a small wire that connects in the middle of the relay. This wire comes from the dash switch and energizes the relay to bridge the two circuits together.

Easiest way to check is have someone press and hold the switch while you listen for the relay to "click" shut. If it does not click, you will need to check that power is being sent with a meter. Likely the relay is bad, fuse is blown or the switch is bad. Those switches get worse with age and tend to be troublesome.

The door switch controls a relay underneath the front hood. These go bad a lot as they require constant energy (latched all of the time) They also get hot and are known to kill your house batteries if left on for a couple months.

[lesvoyageurs]

Thank you so much for this information! We have spent hours trying to determine what is wrong with our dashboard switch and finally took our motorhome to a mechanic and then to an airstream restoration specialist. But neither one was able to diagnose the problem and fix it. We won't be getting our motorhome back until next Wednesday, but as soon as we get it we will follow your instructions and hopefully fix the problem quickly. Thanks again!

[DaveFL]

By the way, the first tech was correct but lacked the full answer batwingz gave, the dash switch is only rated to be able to enegize the selenoid not connect the batteries directly When I am paying to have a problem solved I don't want a guy that will start by replacing parts until it finally works, I can do that much cheaper and have. but I then also have the old parts as backup and no labor or shop costs)

[SebasSF]

My 94 classic has a switch that is off or on, not spring loaded- perhaps it was. The small bulb in the switch was broken when I bought the rv and I was not sure when it was on or off. I had a real surprise one day before a trip when my lights and other stuff were behaving really weird until I figured it out. If the switch is on, the relay will heat up and you can feel it warm. There is no need to "fix" it if you know if the switch is on or off...proper labeling or lights. Best to leave it off because if it's warming up, it's probably not rated to be on all the time.

[Mike1997]

I have a 97 Land Yacht WB diesel, 275hp Cummings. Last weekend it had been sitting up for over a month in the Montana winter. Had it plugged into a 110v and ran a small ceramic heater inside to keep it above freezing. This procedure is also suppose to keep the coach batteries charged.

Tried to start and it was clear the motor batteries were weak and almost dead according to the volt gage. According to my manual, pressing the Auxillary Start button and holding it in place while turning the key, will allow the motor to start using power from the coach batteries. The volt gage increased and that's exactly what happened! Once started, I released the Aux button and the volt dropped but quickly rose once the altenater got up to speed. Took it out on the highway for a 20 mile run and everything was normal. Must admit it is cold natured so looking into options around an engine block heater similar to whats on my Jeep Grand Cherokee diesel.