Battery volts on panel reading low

resqguy · 07-20-2013, 05:53 PM

I just picked up a 2004 Vectra 40AD and am going over things. I noticed the house batteries reading a little low (11.9 v) on the panel, when disconnected from shore power. I checked the voltage with the meter at the batteries and they read 12.4v. The chassis batteries also read about .4v difference between the display and what the meter reads at the batteries.

Is 12.4v at the batteries lower than it should be? Any ideas about how to determine what could be causing the drop?

Yoda2405 · 07-20-2013, 06:13 PM

If you can pull the panel display try to measure the voltage going into the panel, that will isolate the problem to the battery/wiring or the one place display.
If the one place wiring reads 12.4 v with your DVM, then the one place display would seem to be the problem. If you read 11.9 v then I would start checking the wiring between the batteries and the coach - grounds are the most likely problem. Check them in the battery area.
12.4 v is a normal voltage for a charged 12 v battery.

Skip426 · 07-20-2013, 06:16 PM

Depending on length of charge time 12.4v could be a little low. If the batteries have been charging for 48hrs with no load , batteries in great condition would show 12.6 to 12.8.
Low read out could be a problem to track down . Can you access the wiring to the onboard meter and check volts with your hand held ? If you get the same lower reading with the hand held then you have a poor connection in the line. If the hand held shows the same reading at the wire as at the batteries then you have a faulty gauge.

And I see Yoda, like everyone else in the forums types faster than I do.

resqguy · 07-21-2013, 08:53 AM

Thanks. I will get at this today and post an update on what I find.

I don't want to get too far ahead or cloud the issue, but I'm having an intermittent issue with all the slides. On a few occasions when I go to extend/retract the slides I will get a "click" sound and nothing else. I'm assuming that is my relay. I can get the slide(s) to work if I hold the switch down or retry it a couple of times. That is what got me looking at the battery level in the first place. When this happened I checked the panel for the battery level and noticed it at 11.9v.

We just returned from a trip on Wednesday. I forgot to disconnect from house batteries on Wednesday night but everything was off (refer, water heter, etc.). I disconnected from the house batteries Thursday afternoon and it remained off until Saturday. The battery measurements are from Saturday afternoon.

resqguy · 07-21-2013, 12:06 PM

I pulled the panel but there wasn't any good place to try to tap into +12. I'm going to try to check it at other points in the coach.

The HWH pump for the slides and jacks is as inaccessible as it could possible be. Any help with locating the relay would be appreciated.

Skip426 · 07-21-2013, 11:12 PM

Don't know if this will help , or just worsen the situation. On my HWH system, the relay is attached to the pump motor.
And for a similar , erratic operation situation , I've had to repair a bad brush ground plate inside the motor it's self.

cbeierl · 07-22-2013, 11:08 AM

Quote:

Originally Posted by resqguy

I pulled the panel but there wasn't any good place to try to tap into +12. I'm going to try to check it at other points in the coach.

The HWH pump for the slides and jacks is as inaccessible as it could possible be. Any help with locating the relay would be appreciated.

The HWH pump and solenoids should be under the entry steps. The top two steps should hinge up for access once you remove the single nut for each under the lip in the center of the step.

rshackleford · 07-22-2013, 11:27 AM

I just diagnosed a similiar issue with my 01 Journey.

I was having odd electrical issues with various symptoms. The most annoying was that the coach wouldn't start sometimes. I had to turn the key 7-8 times before the starter would engage and crank the engine. I assumed it was a bad ignition switch.

Then I started getting low voltage readings on my inside volt meter. I fiannly took out all three house batteries and cleaned the terminals and cable ends on all three. I also cleaned the ends that attached to the fusible link that goes to the charger/inverter. Finally I traced both ground cables, house and engine, to the frame and found the ground lug for both. They were rusted so I removed them and cleaned up everything with a wire brush on a drill.

After that the engine starting issues went away and my inside voltage gauge for the house batteries showed 12.8, exactly the same as what they read directly off the battery.

Then, a few weeks ago my house battereis started showing 11.4 on the inside meter. I got a little discouraged since I thought I had fixed the issue. This past weekend I discovered a light on in one of the basement storage bays. Turned it off and my inside vlotage gauge reads 12.8 again.

I was a little surprised by the amount of current draw and voltage drop the light caused. the batteries even dropped from 12.8 to 12.4 when the light was turned on.

resqguy · 07-23-2013, 07:01 PM

Thanks for the tips. It will be next weekend at the earliest before I can work on the coach.

jerichorick · 07-25-2013, 07:50 PM

Hi resqguy. We just traded our '05 Vectra 40FD. The hydraulic pump is powered by the start battery. We opened and closed with the engine running. Also, your battery voltage seems low. What is it at the battery when the engine is running? How fast does the voltage drop after you shut the engine down and before you load the batteries with the setup routine?