LEDs dimming with water pump on

[sandstormfam]

I've got a new Sandstorm 5th wheel with the LED package. With dual batteries, fully charged, is it normal for all the lights to dim when the water pump is on? I know the pump draws a lot of power, but I thought the low voltage LEDs wouldn't flicker with the extra draw from the pump.My old trailer would do the same thing, but only when the batteries were getting low. Just wondering if it's normal. Still working out the bugs.

[Bama Rambler]

You could have a loose connection either between the batteries and power panel or somewhere in the ground circuit. I'd check the ground(s) wherever they connect to the frame and distribution panel.

[Mr Havercamp]

Originally Posted by Bama Rambler

You could have a loose connection either between the batteries and power panel or somewhere in the ground circuit. I'd check the ground(s) wherever they connect to the frame and distribution panel.

Yes, check grounds.

On our 2017 Rockwood Roo, every ground to frame was attached without removing any paint on the frame whatsoever. just attached with a cheap plated self drilling screw. And for good measure the main, heavy gauge ground wire to frame from the 12V side of the converter, was not tightened at all, it pulled out of its lug by just unscrewing and moving the converter.

[RSchleder]

Our Wildcat MAXX is all LED and there is not a flicker or dimming when the water pump turns on. I believe you either have a electrical issue or your batteries are less than optimum.

[SeaDog]

X2 with the grounds. Also at your converter tighten all the connections. basically go thru and tighten all electrical connections.

[Flybob]

Water pump should not draw enough current to lower voltage if you have two fully charged batteries. Check connections. If all it well then check actual battery condition using hydrometer.


Charged
Specific Gravity
100% 1.255-1.275
75% 1.215-1.235
50% 1.180-1.200
25% 1.155-1.165
0% 1.110-1.130

[camaraderie]

How do you know your batteries are fully charged and good??

Suggest the EASIEST way to check if you have a battery or related issue is to PLUG in at a park...then run your water pump and led lights. If you still notice a dimming...you likely have a grounding or other installation problem OR a bad converter supplying 12V to your coach.

If you have NO dimming...you have a battery problem. The lights in your unit telling your battery condition are worthless. Get a volt meter to start:
1. While PLUGGED IN...take a voltage reading at the output terminals of your converter. Should be MINIMUM 13.2V...maximum around 14.5V If not...you have a bad converter...if no reading...check for blown converter fuses.
2. If you have good voltage at the converter... check at the battery terminals for voltage...same readings indicate a good charging circuit.
3. Leave plugged in or a day or more. Everything in the unit turned off EXCEPT the battery switch...make sure you're getting 13+ Volts at the battery terminals before you walk away.
4. Come back...unplug... and REMOVE the negative wire from your batteries. Go away for 24 hours...then come back and take another reading on the battery terminals. It should be 12.6V or slightly higher if new. If 12.4 -> 12.6 you have some wear on your batteries. If less than 12.4...get new ones from your dealer as you have lost significant capacity and you are entitled to something that hasn't been abused on the lot.

Hope this helps and good luck.