Batteries Last A Long Time but do NOT charge while towing.

[midasman]

My '06 HR Ambassador has the 4 original batteries. Like tires, they may have been installed in 2005 when the chassis was delivered. So, they are between 7-8 years old (unless they were replaced in the 2 1/2 years before I got it (early 2009) though not too likely. SO, nervously I saddled up and went out to the coach with my trusty hydrometer to read the specific gravity. To my AMAZMENT, ALL cells read around 1.280! I had assumed they were OK because they only needed water every 3 or 4 months.
They do, however, stay fully charged 95% of the time and we dry camped at the Oshkosh AirVenture for 8 days, but that was the only longer term dry camp.

For some reason though, the batteries do NOT charge off the alternator. To test this, I unplugged for 20 minutes and then cranked up. Battery voltage did NOT change. When I plugged in again they charged at 60amps for 15 minutes or so and then tapered. Any thoughts???

[midasman]

Wow! It amazes me of the knowledge bank here on the forum! Yep, it does have the trombetta relay right where you guys said. I have had relatively few problems with my '06 Ambassador EXCEPT I have been plagued by leaks. Always wet by driver's left foot. Finally got a RV guy to recaulk and my local glass company R&R'ed driver's window and resealed. Gasket had shrunk and especially where the front cap overlaps. Now it's the RR slide. I think the biggest problem is that the coach has been out in the southern sun all it's life. Last year I finally built a cover and do not hate the rain anymore! Oh--just replaced the Coachstep motor. I do feel that the Roadmaster is ROUGH riding but it may be that I went with XZA2, but the J weight rating--too stiff! Original Goodyears were H series--much smoother.
Thanks, guys.
Pete

[kdk]

Midasman; Temperaturecontrolman is correct with the trombetta relay being bad. It is mounted above the batteries on the wall with large red cables attached to it. He is also right that the replacement should be one with silver contacts. Google trombetta for a phone number and they will put you in touch with a distributor in your area as they will not sell directly to you. I had the same problem and after taking the relay apart and cleaning the contacts it still only worked for a short time. Replaced the relay with a silver contact one and have had no more problems for 4 years.
Blessings KDK

[TempatureContro]

We have 06 Monaco Knight(same thing you have). The Trombrella relay is bad in yours. The original has copper contacts. Be sure to get the replacement one that has silver contacts-it will last longer. You can find it on line for<$60.00. Had to replace ours last Spring. Exact same symtoms. Had to replace the 2 original chassis batteries this fall. Our 4 house batt are all original-so far so good!

[midasman]

There is a relay there with a blue wire and a white wire coming from the house shut off switch. Also my parallel switch didn't work when the coach wouldn't start a few months ago...

[wolfe10]

You have either a relay/solenoid to charge house battery from alternator or a diode-based isolator.

Find out which you have and then let us know-- test procedure is very simple (but different).

[Artum_Snowbird]

My 07 Regency had a bi-directional relay as part of the charging system. It sent power to the chassis battery if the generator was running or it was on shore power, or sent power to the coach if the engine was running.

Put your voltage meter onto the battery posts, and check to see what you have first with nothing running, then in each direction.

I know I had to take the relay apart and clean the contacts once.

[Davehrn]

Relay that runs off of ignition connects chassis battery to house battery... follow big red wire from battery ... I will go to starter... the other to the house battery