Diesel start batteries

Solar panels are not damaged by being shorted to themselves. Did you mean he damaged the controller?

OK, You need to find out why the isolator solenoid is not being energized. Could be something simple like a fuse. Then the house batteries will charge from the alternator.

If the rig design is to not charge the chassis battery on shore power then you should correct that with say a Trik L Start or a 2A battery maintainer.

Something is wrong with having to replace batteries every 2 years. Kept charged it should be 5+ years. Consider buying a $50 Sears clampon DC ammeter and find out what is draining your batteries as it would have long ago paid for itself with increased battery life.

Why did you switch to 12V house batteries? 6V are better suited for house batteries, more power and greater number of recharge cycles. Otherwise 12V are OK.

The Isolator/Emergency Start is a solenoid that is not energized (I checked yesterday). The solar panel can be eliminated as suspect because several years prior a serviceman shorted out the solar panel and I removed the solar panel and pulled it's fuse in the BCC. Also, I had the parasitic drain before and after the solar panel malfunction.

I took the vdc readings within 4-5 minutes of engine start.

The diesel and coach batteries are less than 2 years old and I have had to replace all 4 batteries about every 2 years $$.

Could this problem be connected to when, in 2005, I had Sear's convert the series 6vdc batteries to parallel 12vdc batteries? Where possible I have hand traced battery cables to their intended destinations and not found anything obviously wrong.

The analog gauge and panel indicator both have limited usefulness. In fact the red diesel battery light is incorrect given the digital numbers you posted. Like the typical tank lights which mostly help the salesman to sell the unit - "it comes equipped with indicators for the tank levels..."

Your digital voltage numbers are useful and don't necessarily show any problem. Without shore power and disconnect any solar turn on the headlights for 10 minutes. Then start and quickly check the chassis voltage which should be 14.4V+ and taper to 13.4V+ float. Also after 2+ minutes and perhaps longer the house battery should show a charge.

What type of battery isolator do you have?

Before further testing, I would like to add two driver area indicators that may help.
1. The dash console analog diesel battery meter does not function until the key is switched ON. Once ON the meter reads below normal, which would be the midpoint (or twelve o'clock) position. When the alternator begins charging the indicator will move to slightly above normal. The meter ranges from 0 to 18vdc with only a midpoint scribe line for Normal (no numbers other than the zero and the 18).

2. Also there are level panel indicators for the diesel batteries that are 4 vertical mini-lamps that when lit go from red (discharged), red & yellow (below normal), red & yellow & green (normal), and finally red & yellow & green & green (charging).
My indicator lights with key off are usually red & yellow, going to green or double green when charging.
The diesel battery lamp goes to red with key switched ON and stays there even while driving.

I hope this makes sense :h Thank you for your patience and help. I will continue next week after our Easter celebration.

Actually 12.8V house could be OK depending upon any electronics that controls the isolator as there could be a delay before it's engaged. But it should within a few minutes connect the banks together.

And I've had several of the not so go Intellitec isolation relays fail.

How long after starting did you wait before checking the voltage?

Two things, the drop in chassis battery from 12.8 to 12.3 is OK if it is due to the very high amp draw of the intake manifold heater. But, were you to release the key (i.e. no more load) it should return fairly quickly to the 12.6+ reading. If not, fully charge and have the chassis batteries load tested.

The 12.8 reading at the house battery with engine at high idle (where the alternator should be charging both battery banks) is a problem.

Do you have a diode-based battery isolator or solenoid-based battery isolator. The isolator is the first suspect area when one bank shows charge and the other does not.

Sorry I took so long to reply. Texas, as you asked, here are the battery readings I took.

Chassis w/ign. off - 12.8vdc
House w/ign. off - 12.8vdc
Chassis w/ign. on - 12.3vdc
House w/ign. on - 12.8vdc
Chassis w/engine running - 13.9vdc
House w/engine running - 12.8vdc

The reading were taken after I disconnected the temporary battery charger and with the Xantrex 458 completely disconnected. Shore power is disconnected. I will take more readings with the Xantrex connected and post when I can. Thanks again!

DaveN wrote:
Putting my correct use of the meter aside and during further inspection, I heard air escaping near the front wheels but the rain kept me from getting underneath to discover the source. Could the amp draw be from the air compressor running - which doesn't start until after the engine is running? The Freightliner/Fleetwood interface electrical drawings are incomplete, erroneous, and downright confusing. Btw, the daytime temperatures here are in the 60's and 70's and the diesel batteries were fully charged before starting so the alternator output should minimize within a reasonable amount of time.

The air sound you hear may be the drain valve(s) on the air
tank(s) . They are located in close proximity to the front wheels . I recently pulled the lanyards to drain my tanks and one of the valves didn't want to close completely. After jiggling the valve and filling and draining the tank a few times, it did finally seat and close.

Dave,

Tell us the voltages at each battery bank under the following conditions:

Shore power disconnected, engine off (i.e. batteries at rest).

Shore power on, inverter/charger on.

Shore power disconnected, engine on and at high idle.