Community Forums

Sbrownstein · 08-08-2021, 09:33 AM

now that is one for the books... I guess the builders had to get power for the system from somewhere and the backup lights are probably the least used circuit on an RV (generally no trailer connections on the 7 way center pin.)

Now, of course...how did yours blow?

Flight Test · 08-08-2021, 11:53 AM

I too have wondered why it was blown. I put the same amperage fuse (15A) back in that came out of it and so far so good. I drove around for a bit and rechecked, and the coach batteries are still getting charged. The new Cole Hearse relay seems to be working good so far.

Ray,IN · 08-08-2021, 01:59 PM

Quote:

Originally Posted by cbeierl

As designed the (typical) Winnebago Battery Boost switch activates the battery boost solenoid via a chassis run-only power source in its normal resting position. When momentarily depressed the switch activates the solenoid via an always-on power source. This means that the battery banks are connected together whenever the engine is running (or the switch is depressed).

(Note that some more recent coaches may have a Battery Isolation Manager or other smart electronics to handle this function instead.)

Study the schematics again. The momentary boot switch only holds the solenoid in while the switch is depressed. Thus the word momentary is used when discussing this switch.

Flight Test · 08-08-2021, 02:14 PM

As shown in the schematics the switch in the normal position provides power to the battery boost solenoid when the engine is running. In addition you can also provide power to the boost solenoid by pressing the switch ( even if the engine running portion is not energized ).

It seems most problems are from a bad boost solenoid relay but my issue was a blown fuse coupled with a bad solenoid.

cbeierl · 08-08-2021, 02:27 PM

Quote:

Originally Posted by Ray,IN

Study the schematics again. The momentary boot switch only holds the solenoid in while the switch is depressed. Thus the word momentary is used when discussing this switch.

I have studied the schematics. The top end Ultimate Freedom/Advantage coaches such as yours are different in that they have a B.I.R.D. (Bi-Directional Isolator Relay Delay) to manage the connection of the two battery banks.

For most other Winnebago coaches (including the OPs) until the more recent ones, at least some of which DO have a B.I.R.D. or other smart electronic control, the Battery Boost switch is configured as I've described--there are TWO power leads going to the 'momentary' switch. One is run-only power which is active when the engine is running, the other is always active. In its non-depressed resting position the boost switch connects the run-only power to the output. When depressed it connects the always active power to the output.

Jebrice406 · 08-08-2021, 07:44 PM

Quote:

Originally Posted by Flight Test

Thank you so much l1v3fr33ord1,

It took me awhile to figure out your Handle, but it is definitely a good one!

I really appreciate you taking time to help me out. I have checked the big blade fuse at #8 and it was good but I will dig into the under dash fuse box and try to dig out fuse 15. For the life of me I just can’t imagine a much worse place to put a fuse panel deep under the dash of a van with no driver leg room to fit under there.

My plan will be to swap out the relay if the fuse is ok.

I really appreciate the body builder layout book, I did not have that in my reference library. What a great add.

I sure missed the reference to the trailer battery charge fuse when I was looking at the Itasca schematic.

Thanks again, I will send try to send out an update tomorrow.

Hello Flight Test, did you eventually find the problem? What was your fix?

Flight Test · 08-09-2021, 01:58 PM

I was able to get it fixed! It ended up being a blown fuse in slot 12 ( back up lamps) in the fuse box under the dash of the E450. The odd thing was this fuse location was not listed in any of the wiring diagrams I found or was shared by the other members on this forum.

Replacing the boost solenoid fixed the issue with the battery boost switch and finally finding the blown fuse in slot 12 fixed the system to allow the chassis batteries to charge with the engine running.

Have a great day