Luxury Coach Lifestyles - View Single Post

rheavn · 12-03-2011, 12:45 AM

Thanks to all for your suggestions which were very helpful. Hopefully this post will help some one in the future diagnose their alternator problem.

The first symptom I noticed was the dash voltage meter dropped to about 11 volts. Newell had me check the voltage on the battery cable at the center post of the battery isolator. Voltage was zero. Newell tech felt it was the alternator.

The following tests will determine whether the zero voltage is the alternator or the voltage regulator. Remember my system has a remote voltage regulator. First test is the ground for the voltage regulator, which tested good. The voltage regulator has a four wire connector marked(left to right) "I", "A", "S" & "F". "A" should have battery voltage present at all times and it did. "I" should have battery voltage with the ignition is on and it did. The next test was to start the coach and jumper "I" to "F"--only connect for a second or two as you should see an immediate voltage jump, which could damage the batteries if left connected longer. My test results were negative, no voltage jump, so the alternator is bad. If I had seen a voltage jump when jumping "I" to "F" then the voltage regulator would be bad. If the battery isolator is receiving alternator voltage at the center post, but either one or both battery banks are not receiving charging voltage then the battery isolator is bad.

I posted some photos to help you visualize my explanation. Photo #1 is an overall photo. #2 is a photo of voltage regulator inside the stainless cabinet. Photo #3 is close up of voltage regulator and wiring harness--you can see the wire markings. Photo #4 shows the battery isolator.

Hope this helps someone...........................

12-03-2011, 12:45 AM	#7
rheavn Senior Member Join Date: Feb 2010 Posts: 433	Thanks to all for your suggestions which were very helpful. Hopefully this post will help some one in the future diagnose their alternator problem. The first symptom I noticed was the dash voltage meter dropped to about 11 volts. Newell had me check the voltage on the battery cable at the center post of the battery isolator. Voltage was zero. Newell tech felt it was the alternator. The following tests will determine whether the zero voltage is the alternator or the voltage regulator. Remember my system has a remote voltage regulator. First test is the ground for the voltage regulator, which tested good. The voltage regulator has a four wire connector marked(left to right) "I", "A", "S" & "F". "A" should have battery voltage present at all times and it did. "I" should have battery voltage with the ignition is on and it did. The next test was to start the coach and jumper "I" to "F"--only connect for a second or two as you should see an immediate voltage jump, which could damage the batteries if left connected longer. My test results were negative, no voltage jump, so the alternator is bad. If I had seen a voltage jump when jumping "I" to "F" then the voltage regulator would be bad. If the battery isolator is receiving alternator voltage at the center post, but either one or both battery banks are not receiving charging voltage then the battery isolator is bad. I posted some photos to help you visualize my explanation. Photo #1 is an overall photo. #2 is a photo of voltage regulator inside the stainless cabinet. Photo #3 is close up of voltage regulator and wiring harness--you can see the wire markings. Photo #4 shows the battery isolator. Hope this helps someone........................... Attached Images __________________ Steve Newell