Only 6-7v output on battery power

[KaptainK]

‘98 RT 200 versatile
-Shore power works fine- AC and DC
-When on house battery, no DC
-Only getting 6+ volts at DC panel
-battery shows 12.4v at terminals
-When I push the ‘test’ button to read tanks and battery level, the led lights in the ceiling will come on while button is held only.

Anybody know what to check?
** My house battery only seems to have a + red cable to the isolator, and a black - to chassis. Don’t I need another connection from battery plus to the converter? I don’t see one.
- I found that the ground cable was broken where it attaches underneath by the fuel filler. I replaced the ground connection (comes in on the uninsulated wire)
-I’m wanting to check the red DC power cable and follow it back from the DC board. Shouldn’t that go to the battery?

[booster]

Is the isolator under the hood? If so, you may have binding post somewhere where the cable from under hood, cable to the battery, and a cable to fuse panel and charger. That is how our 07 Roadtrek 90 was wired.

[KaptainK]

Checking power on the Red or Blue wire yields the same result...6-7v

Battery switch ON or OFF seems to give the same result also

With Starting battery only and no house battery, same reading at DC panel

[booster]

Originally Posted by KaptainK

Checking power on the Red or Blue wire yields the same result...6-7v

Battery switch ON or OFF seems to give the same result also

With Starting battery only and no house battery, same reading at DC panel

You didn't mention a blue wire. Where is it?

[KaptainK]

Originally Posted by booster

You didn't mention a blue wire. Where is it?

Yep, I did! Red or Blue to Green (ground) give same results.

[KaptainK]

My isolator is up front on the passenger frame rail.
Right post- From battery and back to van wiring.
Center - yellow wire I think comes into fuse box.
Left post- To the rear for B+ (I assume).

[KaptainK]

I do get 12+ volts at both big terminals on isolator. I think it is charging from isolator to house battery. I don’t understand where 12 V goes to the converter.

[KaptainK]

Does the Left Post to house B+ split someplace and go to the converter AND the rear B+ terminal? Maybe it does, and the converter is fried?

[KaptainK]

I'm getting 6v-7v on the DC side of the converter, with or without a house battery hooked up. It will charge the house battery when it is hooked up, but it isn't getting through. I'm confused on how the 12v from the rear battery gets to the converter? Unless that single feed of the isolator splits and goes to converter and house battery.

[KaptainK]

Getting closer...I just hooked up a battery directly to the RED and GREEN terminals on the DC block of the converter. 12v stuff works fine that way. I need to look at that RED incoming wire to the DC panel evidently.

[markopolo]

1998 Chevy?

If so, the isolator setup doesn't look right at all. The Chevy needs a 4 post isolator as far as I know. The isolator in the photo looks to be 3 post so it's missing the "E" post (external excitation connection). It appears that the isolator is actually bypassed so only the chassis battery will get charged. The E wire appears to be on the center post & the alternator wire that should be on the center post has been moved to an outer post. Maybe it was a failed isolator or wrong isolator just left there & bypassed. The small red wire is probably the sense wire. You'd get 12V on the outer posts because they're connected to batteries.

Here's a PDF link to the wiring:
http://www.cooperindustries.com/cont...ST_180012q.pdf

[KaptainK]

LOL. From the way this thing has been hacked up, I'd say you're probably right! Oh lordy.

[KaptainK]

Yes, you are correct. That is the wrong isolator. It tied both batteries together, and would use both to start or for house power. It also kept the rear set of cables live, even with no battery in the rear. I disconnected the isolator from the house battery for now. I finally solved my power problems with DC power in the house. It turned out to be rotten cables, and a bad battery switch solenoid. I worked on the cables and replace the solenoid, and I now have DC power to the house via the battery, battery charging when plugged in, and AC to DC converter 12 V power. I will install a new isolator to charge while driving. Thank you very much for the help.

[markopolo]

You're making real progress
Here's a service manual for the Intellitec relay -> http://techsupport.pdxrvwholesale.co...-00055-000.pdf

Sounds like you've replace yours but, if you still have original, might be worth working through the troubleshooting steps to see if it can be made to work and kept as a spare.

[KaptainK]

Here’s the new isolator. I may relocate it while I’m at it. The old one is covered in road splash and rust.