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1987 Grandvilla Headlights Dim

June 19, 2017, 01:46:15 pm

We have a 1987 Grandvilla ORED with CAT engine.  The electrical system has several problems.

Headlights:
1) The headlights are dim and then fade to almost no light then cycle back up to some light and continue through this cycle. 

2)  Related Information:  The engine has a new alternator and the voltage meter goes up and down.  The chassis mechanic who replaced the alternator could not figure out why the voltage meter kept bouncing around.  New Coach and New Engine batteries installed this spring.

Any suggestions how to prevent the headlights from going through the low light cycle?

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Re: 1987 Grandvilla Headlights Dim

Reply #1 – June 19, 2017, 03:03:38 pm

Start by looking at the headlght switch, all current flows through it.  Make sure all grounds are clean and secure.  Do you get low voltage when the boost switch on? Do you have this problem when on shore power?

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Re: 1987 Grandvilla Headlights Dim

Reply #2 – June 19, 2017, 03:10:11 pm

Alternator/voltage diagnosis comes first.

THEN, IF, repeat IF all the power for the headlights does go through the switch (vs the switch just controlling relays) the fix is EASY.

Let us know if you have head light relays or if indeed power does go through the switch.

If no relays, adding relays will cost less than $20 and make a MATERIAL improvement in light.

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Re: 1987 Grandvilla Headlights Dim

Reply #3 – June 19, 2017, 03:10:45 pm

Here we go again. Key word......NEW alternator. You must make sure that alternator has been modified for DUVAC system or you will have problems.

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Re: 1987 Grandvilla Headlights Dim

Reply #4 – June 19, 2017, 03:50:01 pm

Twig may have a good insight into the problem. Using a digital voltmeter, check (and write down) voltages at the alternator, batteries, isolator, ignition solenoid under the dash with the engine running. Digital voltmeters are very inexpensive and a very helpful diagnostic tool. If you don't have it, download the 12V schematic for your coach and have a copy shop blow it up for easy reading.

Another good reason to have your local electrical shop rebuild your existing alternator instead of ordering one.

Always good when you have a problem to go back to the last thing you replaced or worked on.

Pierce

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Re: 1987 Grandvilla Headlights Dim

Reply #5 – June 19, 2017, 06:46:30 pm

Thank you all your comments/suggestions are sure Great!

The engine mechanic had more knowledge about the CAT engine than Coach issues.  Maybe the alternator is the problem.
I have not tested the headlights on shore power - I will try that next time I hook up.

Other electrical items, maybe related.
The refrigerator and ice maker are also not working since the mechanic worked on the vehicle.  Refrigerator works on propane and now has trouble on electrical, the ice maker is also now broken.  GFCI breaker was replaced by Camping World and continues to trip.

The volt meter/tester will be pick-up this evening and I share what I learn.

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Re: 1987 Grandvilla Headlights Dim

Reply #6 – June 19, 2017, 06:53:53 pm

try very hard not to do Camping World

On an older coach like yours, Mechanics can cost a huge amount relative to the value of the coach. You will be surprised by what you can do yourself, saving a lot of $$$ and getting to really know your coach.

Tim Fiedler

Sure Start Soft Start

www.tcerdirect.com generator-gas-prod 630 240-9139
Gen-Pro

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Re: 1987 Grandvilla Headlights Dim

Reply #7 – June 19, 2017, 07:26:15 pm

Check the chassis grounds and make sure that the headlights has the ground strap  from the light socket to the frame near the jack pump.
 
Of course check last place messsed with first, esp if the stuff worked prior to the service. 

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Re: 1987 Grandvilla Headlights Dim

Reply #8 – June 19, 2017, 08:19:04 pm

Foretravel in those days did not have a green ground wire from each circuit to a grounding area. 

Ground to frame like older cars. 

Lots of flickering lights because of this, 

Normally running lights,  not headlights

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Re: 1987 Grandvilla Headlights Dim

Reply #9 – June 19, 2017, 08:52:52 pm

Bad grounds can make guage erratic

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