Auxiliary battery issues

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WTSMatt

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I’ve installed a Renogy 200ah AGM battery, 2-100w Renogy solar panels and Redarc 1225BCDC controller in/on the bed and rack of my 2016 F150. I have everything wired but the battery isn’t charging off the solar or starter. It remains stuck in FLOAT stage charge. The 1225BCDC and auxiliary battery are grounded to the frame together. The solar is grounded to the auxiliary battery. After speaking with REDARC they are saying to install ground cables between truck bed and chassis. I’m confused. Do I do that, not even 100% sure what that means, or run all my grounds to starter battery or something else maybe? I’m getting power from solar and starter battery but it’s getting ‘stuck’ in the controller. The diagram below is how I’m currently wired.
 

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grubworm

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troubleshoot it in pieces. disconnect the truck from the system and disconnect the solar. hook up your battery to the charge controller and set the charge controller for the AGM battery. normally, you hook the controller to the battery and select the battery you have. do that and then hook up your solar to the charge controller and see if that works. in good sunlight, you should read around 13-14vdc coming in from the solar. i have the renogy 100w panels and controller on my square drop trailer and i hook to the battery first and select the battery type, then hook up the solar. i dont feed from from my alternator, so i dont know how your controller works between panels and altenator, but i would at least get my solar set up and working and then figure out the input from your altenator. i also have a renogy solar panel and controller for my camper shell and i did the same where i hooked the controller to the battery, selected the battery type, then hooked up the panels and everything went fine...i'm reading the input from the panels and its usually 13-14vdc and everything works fine. you might need to figure out what needs to be done to select between solar and altenator...not sure if its automatic or if you need to input something to the controller to let it know you have 2 different inputs
if you can get the solar panel input working, then you can rule out it being a faulty controller
i have solar panels on my house, camp trailer, shop, and truck camper shell and none of the panels are "grounded"...they are silicone wafers wired together in a frame, no grounding that i'm aware of other than the negative wire being called a ground in DC.

your solar panels have a black and red wire with the black being negative. if you use the black wire directly off the panel, that is called a "floating" ground whereas with a vehicle, the black wire essentially goes to the chassis and then what ever you hook up has that black wire going to chassis...that is a "chassis" ground with the chassis being the common link for the negative (ground). that is more susceptible to problems with corrosion and good contacts, so if you wire the black wire directly to the power source and the load, then you eliminate the chassis as the middleman and have a more direct path.
 
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9Mike2

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+1 to above. A lot of truck beds are on rubber and don't have a great ground. As working on Boom Trucks , redundant grounds are needed, we also could not have any grounding at the boom end or the operator would be dead or permanently springy hair
 
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WTSMatt

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troubleshoot it in pieces. disconnect the truck from the system and disconnect the solar. hook up your battery to the charge controller and set the charge controller for the AGM battery. normally, you hook the controller to the battery and select the battery you have. do that and then hook up your solar to the charge controller and see if that works. in good sunlight, you should read around 13-14vdc coming in from the solar. i have the renogy 100w panels and controller on my square drop trailer and i hook to the battery first and select the battery type, then hook up the solar. i dont feed from from my alternator, so i dont know how your controller works between panels and altenator, but i would at least get my solar set up and working and then figure out the input from your altenator. i also have a renogy solar panel and controller for my camper shell and i did the same where i hooked the controller to the battery, selected the battery type, then hooked up the panels and everything went fine...i'm reading the input from the panels and its usually 13-14vdc and everything works fine. you might need to figure out what needs to be done to select between solar and altenator...not sure if its automatic or if you need to input something to the controller to let it know you have 2 different inputs
if you can get the solar panel input working, then you can rule out it being a faulty controller
i have solar panels on my house, camp trailer, shop, and truck camper shell and none of the panels are "grounded"...they are silicone wafers wired together in a frame, no grounding that i'm aware of other than the negative wire being called a ground in DC.

your solar panels have a black and red wire with the black being negative. if you use the black wire directly off the panel, that is called a "floating" ground whereas with a vehicle, the black wire essentially goes to the chassis and then what ever you hook up has that black wire going to chassis...that is a "chassis" ground with the chassis being the common link for the negative (ground). that is more susceptible to problems with corrosion and good contacts, so if you wire the black wire directly to the power source and the load, then you eliminate the chassis as the middleman and have a more direct path.
Gonna give that a shot and see what happens. I’ll update with results
 
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Road

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Good advice above.

Inspect your ground attachments points; wirebrush to bare metal; attach a cable to bare metal bed to bare metal on frame if grounds are only to the bed now, etc.

There also exists the possibility, though, that your 200ah AGM is fully charged from daily running and solar exposure--especially if new and not being used by much draw daily--so the REDARC controller sees that and is only sending minimal current for float stage.

.
 
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LONO100

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Just a suggestion, but try running the ground to the starting battery. Frames are heavily coated to prevent rust so no matter how hard you have run a brush wheel or wire brush or sandpaper on the frame, you may not be getting proper contact to ground. I don't know how you have the wires grounded to the frame, but if you are running a plated bolt/screw that is pinching a ring terminal to the frame, and the frame isn't scrubbed down to bare metal, you will get an inconsistent ground at best. Running your ground to the starting battery is the best way to ensure you are getting proper ground. You also didn't mention what gauge wire you are running to tie everything together. Make sure you are running the recommended gauge based on your setup. Sometimes the controller will have a safety feature on it that will keep it from charging if it thinks it may burn itself, or when the batteries are at a voltage that is below the threshold for the controller to begin charging. That threshold is usually somewhere below 10.0V so get a multimeter and make sure your batteries are properly charged before you try to run the system. Hope this helps.
 
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Duval Dummies

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Good advice above.

There also exists the possibility, though, that your 200ah AGM is fully charged from daily running and solar exposure--especially if new and not being used by much draw daily--so the REDARC controller sees that and is only sending minimal current for float stage.

.
This is very true. If you have nothing drawing off that battery the 1225 will remain in float mode due to the battery level being at a high enough level to not need a charge.

I have a very similuar system. I run a 1225 with a Cascadia solar panel. My solar panel is grounded to my chassis, the 1225 the fuse block after it are all grounded to a ground block then to the chassis as well. I have no issues at all. Not everyone likes the chassis grounds, but they have always worked for me. Hope this helps.
 
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smritte

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Even though this may or may not fix your problem, run a 6-8 gauge wire from your body, bed to your frame and one from your batteries to frame if you don't have one yet. . Your engine should already have a good feed to your battery. Body grounds are commonly overlooked. Your entire vehicle is tied to the body with normally a 12-10 gauge wire (except alt and starter). As we add things in the wiring needs to be updated.
 
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