Community Forums

traveler of california · 03-24-2014, 07:48 PM

After a long stay at a CG I notice that my voltage for the engine battery goes down over time. My question is at what voltage level should I be concernd about the coach not starting without the need to call for a jump start?

I do not have a trickle starter and have not needed one since I have had the MoHo.

Nick, Journey '01

**TonyDi** · 03-24-2014, 08:37 PM

At 12.2 volts your battery is 50% charged. Problematic starting at that point if you have to crank it a bit. A trickle charger is a cheap way to assure yourself that your batteries will always be charged.

Ray,IN · 03-24-2014, 08:38 PM

How do you read battery voltage now? While on shore power, read starting battery voltage, it should be 13.8 when batteries are fully charged. In the neighborhood of 12.2 V is my safe zone in warm weather. Are you saying your coach used to keep the chassis batteries charged and now it does not? If that is the case, your BIRD relay is bad and must be replaced. Practically every MH built in the last 15 years has a BIRD relay to keep chassis batteries charged while plugged into 120VAC. My 2000 Winnebago Ultimate Freedom does, a 2001 Journey should too.
What is a BIRD relay?

BFlinn181 · 03-24-2014, 09:16 PM

If your plugged in to shore power, ALL your batteries should be maintained by the converter/charger unless you have a problem with your B.I.R.D. A relay might be bad or have bad contacts. Do your house batteries charge on the engine alternator? Does your 'Battery Boost' switch work? All these functions are part of the B.I.R.D. circuits and relays.

wa8yxm · 03-25-2014, 09:49 AM

Ok: Some RV's have bi-directional isolators. .These look at the voltage and if EITHER side shows 13+ (NOTE: I do not know the trigger voltage) they connect so all batteries are charging.. Should both sides drop to 12.6, (Resting on a fully charged) they drop out.

Other RV's have one-way Isolators. They sense the ending and if it is running (Ignition on) they connect

In both cases they connect AFTER a time delay.

IF your chassis voltage is going down down down.. You need a Trick-L-Start this .. Is the other half of a bi-direcitonal system.

Simply 3 wire hook up.. Right at the isolator solenoid you find all 3 connections) it charges the chassis off the house system.. I recommend you look into it.