RV.Net Open Roads Forum: Tech Issues: Dashboard Alternator light

RV Blog

  |  

RV Sales

  |  

Campgrounds

  |  

RV Parks

  |  

RV Club

  |  

RV Buyers Guide

  |  

Roadside Assistance

  |  

Extended Service Plan

  |  

RV Travel Assistance

  |  

RV Credit Card

  |  

RV Loans

Open Roads Forum Already a member? Login here.   If not, Register Today!  |  Help

Newest  |  Active  |  Popular  |  RVing FAQ Forum Rules  |  Forum Posting Help and Support  |  Contact  

Search:   Advanced Search

Search only in Tech Issues

Open Roads Forum  >  Tech Issues

 > Dashboard Alternator light

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 8  
Prev  |  Next
Sponsored By:
BFL13

Victoria, BC

Senior Member

Joined: 02/15/2006

View Profile



Posted: 08/01/21 03:16pm Link  |  Quote  |  Print  |  Notify Moderator

So if that light on means the alternator is shut down, the only amps coming in are from the solar and batteries. Not many solar amps, so battery will run down but with the house batts also on line, that would take longer.

The solar controller would stay in Bulk but not be able to keep the battery voltage at 14.6 for long. What happens next?

In my test when the charger was removed, the voltage went back down to spec, but the light stayed on. I don't know if the alternator came back on. It did when I restarted.


1. 1991 Oakland 28DB Class C
on Ford E350-460-7.5 Gas EFI
Photo in Profile
2. 1991 Bighorn 9.5ft Truck Camper on 2003 Chev 2500HD 6.0 Gas
See Profile for Electronic set-ups for 1. and 2.

theoldwizard1

SE MI

Senior Member

Joined: 09/07/2010

View Profile


Offline
Posted: 08/01/21 07:06pm Link  |  Quote  |  Print  |  Notify Moderator

RLS7201 wrote:

Well now that every one is through guessing, here is what's happening with your alternator light.
The alt light gets a + voltage from the dash when the key is turned on. The light sees a - voltage on the other lead from the alternator when the engine is NOT running and the alternator is NOT producing.

Sorry, you information is more than 20 years put of date !

IT DOES NOT WORK THAT WAY ANY MORE.

theoldwizard1

SE MI

Senior Member

Joined: 09/07/2010

View Profile


Offline
Posted: 08/01/21 07:09pm Link  |  Quote  |  Print  |  Notify Moderator

BFL13 wrote:

So if that light on means the alternator is shut down, ...

Your 1991 E350 is "old school" and works the way others have stated.

Your Chevy likely does not work the same.

BFL13

Victoria, BC

Senior Member

Joined: 02/15/2006

View Profile



Posted: 08/01/21 08:13pm Link  |  Quote  |  Print  |  Notify Moderator

OK, so with over-voltage with the new vehicles (is the OP's that new?) and the battery red dash light comes on from the solar's voltage being over spec, does the alternator shut down or not?

If it does,, will it come back on by itself if the voltage is reduced to within spec (by adding load maybe)

Are there model years where it won't matter like my 1991, but it does matter starting about ? year, where the alternator does shut down, but then later years than that ? year, the alternator stays on and just the light stays on too?

If so, then members will know what to do depending on what year their RVs are.

I had that engine stumble reported earlier, but that 2016 van is a Fiat, made in Turkey with parts from everywhere, so not sure it is typical.

* This post was edited 08/01/21 08:23pm by BFL13 *

eric1514

AZ ID

Senior Member

Joined: 09/10/2007

View Profile



Good Sam RV Club Member

Offline
Posted: 08/01/21 08:35pm Link  |  Quote  |  Print  |  Notify Moderator

Well, I'm confused.


2006 Isata Touring Sedan 250


pianotuna

Regina, SK, Canada

Senior Member

Joined: 12/18/2004

View Profile


Online
Posted: 08/01/21 09:28pm Link  |  Quote  |  Print  |  Notify Moderator

eric1514 wrote:

Well, I'm confused.


lol welcome to rvnet!!!


Regards, Don
My ride is a 28 foot Class C, 256 watts solar, soon to have SiO2 batteries, 3000 watt Magnum hybrid inverter, Sola Basic Autoformer, Microair Easy Start.

dougrainer

Carrolton, Texas

Senior Member

Joined: 06/11/2007

View Profile


Offline
Posted: 08/02/21 08:50am Link  |  Quote  |  Print  |  Notify Moderator

RLS7201 wrote:

Well now that every one is through guessing, here is what's happening with your alternator light.
The alt light gets a + voltage from the dash when the key is turned on. The light sees a - voltage on the other lead from the alternator when the engine is NOT running and the alternator is NOT producing. When the engine is running and the alternator is producing, the light on the dash sees a positive voltage on both leads and the light is off.
Now when you solar panels gets the line voltage above 14.6, the alternator regulator shuts the alternator down and the dash light sees a - voltage on the lead to the alternator and turns on.
Nothing wrong with you MH charging system.. The light is doing what it should.

Richard


You seem to think people are guessing. Well, I am NOT guessing. My info is FACT. This is direct from Roadmaster engineers over 20 years ago. The Idiot light will work with both the Alternator zero output and OVERVOLTAGE. But, in this case, it is faulting to show OVERVOLTAGE, NOT, that the Alternator has shut down. Doug

dougrainer

Carrolton, Texas

Senior Member

Joined: 06/11/2007

View Profile


Offline
Posted: 08/02/21 09:06am Link  |  Quote  |  Print  |  Notify Moderator

Last, in the past 35 years, I have had 2 Automotive Alternators FAIL and at no time did the Idiot light come on to let me know. The only way I found out was the Vehicle drained the battery in transit. Doug

RLS7201

Beautyful Downtown Gladstone, MO

Senior Member

Joined: 10/26/2002

View Profile


Offline
Posted: 08/02/21 11:14am Link  |  Quote  |  Print  |  Notify Moderator

BFL13 wrote:

So if that light on means the alternator is shut down, the only amps coming in are from the solar and batteries. Not many solar amps, so battery will run down but with the house batts also on line, that would take longer.

The solar controller would stay in Bulk but not be able to keep the battery voltage at 14.6 for long. What happens next?

In my test when the charger was removed, the voltage went back down to spec, but the light stayed on. I don't know if the alternator came back on. It did when I restarted.


Pretty simple. When the line voltage drops, the regulator does its job and sends voltage to the rotor winds and the generator goes back to work.

Richard


95 Bounder 32H F53
460/528 stroker
Web Master
MWPSchooners.com
First brake job
1941 Hudson


RLS7201

Beautyful Downtown Gladstone, MO

Senior Member

Joined: 10/26/2002

View Profile


Offline
Posted: 08/02/21 11:20am Link  |  Quote  |  Print  |  Notify Moderator

dougrainer wrote:

RLS7201 wrote:

Well now that every one is through guessing, here is what's happening with your alternator light.
The alt light gets a + voltage from the dash when the key is turned on. The light sees a - voltage on the other lead from the alternator when the engine is NOT running and the alternator is NOT producing. When the engine is running and the alternator is producing, the light on the dash sees a positive voltage on both leads and the light is off.
Now when you solar panels gets the line voltage above 14.6, the alternator regulator shuts the alternator down and the dash light sees a - voltage on the lead to the alternator and turns on.
Nothing wrong with you MH charging system.. The light is doing what it should.

Richard


You seem to think people are guessing. Well, I am NOT guessing. My info is FACT. This is direct from Roadmaster engineers over 20 years ago. The Idiot light will work with both the Alternator zero output and OVERVOLTAGE. But, in this case, it is faulting to show OVERVOLTAGE, NOT, that the Alternator has shut down. Doug


Well Doug you may have good info from Roadmaster chassis but in the OPs case, the Ford voltage regulator stops sending voltage to the rotor windings when the line voltage gets to about 14.6 and the alternator stops producing, thus the dash light sees a negative voltage at the alternator and the light turns on.
I have this very same issue on my Ford based MH and have determined the answer with my VOM.
If you have the opportunity to study the Ford charging system on the OPs MH, you will see the issues the dash light plays. It even provided the necessary voltage to the regulator to get the system started.

Thank you for the technical support and documentation that you have supplied the RV community through out the years.

Richard
`

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 8  
Prev  |  Next

Open Roads Forum  >  Tech Issues

 > Dashboard Alternator light
Search:   Advanced Search

Search only in Tech Issues


New posts No new posts
Closed, new posts Closed, no new posts
Moved, new posts Moved, no new posts

Adjust text size:




© 2021 CWI, Inc. © 2021 Good Sam Enterprises, LLC. All Rights Reserved.