Chassis Isolator engages then disengages

[New RV guy]

Please help.
I have a 2005 Presidio 39a
Has a battery boost monitor reset switch.
To start I have to turn the key on and push the monitor reset switch and it engages the chassis isolator that turns the power on to the dash.
Now when I hit the monitor reset switch I get the lights on the dash for a second and then they turn off. I can hear the chassis isolator engage and disengage.
Had to bypass the isolator today to get home.
Any suggestions would be appreciated.
Thank you,
Mike

[CHS]

Originally Posted by New RV guy

Please help.
I have a 2005 Presidio 39a
Has a battery boost monitor reset switch.
To start I have to turn the key on and push the monitor reset switch and it engages the chassis isolator that turns the power on to the dash.
Now when I hit the monitor reset switch I get the lights on the dash for a second and then they turn off. I can hear the chassis isolator engage and disengage.
Had to bypass the isolator today to get home.
Any suggestions would be appreciated.
Thank you,
Mike

I would guess that if you bypassed the isolator and all worked fine, than that isolator would be bad.
I found this:
How do you know if your battery isolator is bad?
Check the voltage at your batteries. If you are not seeing close to the same voltage at the battery as at the isolator (minus some small voltage drop over the wire), you have another problem. If the voltage is 12.7 volts or below, you are probably only seeing the battery voltage and no charging at all is occurring.

[New RV guy]

I switched out the isolator with one in the battery bay and still same problem.
It seems like there is some sort of time delay in the system when I hit the monitor reset switch with key on it originally would engage the chassis isolator and power up the dash with key on. If I didn’t start it within a couple minutes it would disengage the isolator. Now when I hit the monitor reset switch it powers up just for a second and turns back off. Been trying to find a wiring diagram to see everything it runs through.

[javelin]

Originally Posted by New RV guy

I switched out the isolator with one in the battery bay and still same problem.
It seems like there is some sort of time delay in the system when I hit the monitor reset switch with key on it originally would engage the chassis isolator and power up the dash with key on. If I didn’t start it within a couple minutes it would disengage the isolator. Now when I hit the monitor reset switch it powers up just for a second and turns back off. Been trying to find a wiring diagram to see everything it runs through.

I am not familiar with your coach at all, but from your description about trying both your battery connect relays in the chassis battery application and still having a problem getting ignition power to stay on (both relays would not stay operated – sounds like they are not latching style or they were being turned off by the control system), it would appear that the circuit that operates your chassis battery connect relay and keeps it operational, has a problem. Can’t help with a schematic, but I was wondering if your 2005 coach uses a Vansco multiplex control system to control battery systems in your coach? If Vansco equipped, perhaps all your battery relays (latching or basic powered interconnect style relays that join coach and chassis batteries together under certain voltage and time conditions) are controlled by the Vansco? Search some other forums IRV2 if you don’t get a fix here, as I think there were some issues with Vansco controllers in and around 2005......... but may not be your issue.

[New RV guy]

Thank you for the reply.
Called previous owner. The system uses the Bird system intellitec.
He was the original owner.
RV used to start with just the key.
A few years ago it wouldn’t start unless you hit the auxiliary monitor reset button which powers the big boy chassis isolator. Now hitting the monitor reset switch won’t fully engage the isolator. I’m trying to find the rocker switch to start with that first. Otherwise I’ll run a direct wire with a toggle switch on the dash to turn the isolator on and off.

[OldWEB]

The terminology in this thread is a little confusing.
Here is a copy of a typical BIRD system (All I can find is the gas version), Your Mileage May Vary.
On the last page shows the "typical" three disconnects, Coach (house) Disconnect; Isolator Relay (some call Emergency Start); Chassis Disconnect.
Now the Chassis and Coach disconnects are operated from near the door or where you may have some central control system (you did not answer when asked) and usually the Emergency Start switch (one way to control the Isolator Relay) is on the dash by the steering column.
So what is it you have in addition to a BIRD (if you found it)? Pics are always nice.

[OldWEB]

https://intellitec.com/wp-content/up...-00839-000.pdf


Found the diesel version which just neglects to cover what you may have for Chassis/Coach Disconnects.


So the symptom you describe would tell ME your Chassis battery has no juice and you use the disconnect to give it that from the Coach battery.
Can you use a voltmeter?

[New RV guy]

Thank you for the information.
I’m a little new at this and working on the terminology.
All my Battery’s are 10 months old. Voltmeter reading was 13.2 on chassis battery’s. I’m not sure how to load photos on to the message.
I have my main panel about the stairs that has all the house switches on it and the main house disconnect. All that works fine. When I bought the RV the old owner said I had to turn the key on and push the monitor reset switch which is the bottom side of the rocker switch for the battery boost. With key on and pushing the monitor reset switch the dash lights would come on and I could start the RV.
Now when I push the monitor reset switch the dash lights come on for a second and turn right back off. Come to find out when I hit that switch it engages the Big boy relay isolator back by the Diesel motor on the frame. Replaced the isolator and still the same problem. I had to jump the posts to power up the chassis and get home. Trying to figure what is in my circuit the engages the isolator when the key is turned on.