Voltage Issues

I have a 2017 Platinum and have some electrical/voltage issues. So I have some weird things that have just recently started happening. I have noticed that sometimes my interior map and dome lights will start flickering if I turn them on when driving. For reference they are still the factory incandescent lights. Also I have a 40" light bar that is wired into a switch pro that will flicker as well. I have not noticed any brightening or dimming of the head lights while driving or if I rev the motor. Today the trucks voltage meter was bouncing all up and down from 12v - 14v. I know this because of the scan gauge I have aw well is reading anywhere from 12v - 14v. The voltage fluctuations also do not coincide with revving the motor so there isn't really a pattern. The truck runs and starts fine so im trying to decide it my alternator is on its way out or if my factory battery is on its way out.

 

did you notice any chewing on the electric cables ? maybe mice
It's that time of the year.

 

I haven't noticed any chewing or nests of any sort. I have checked all of my grounds as well and they all seem clean and tight. Its weird because its random some time it happens sometimes it doesn't.

 

did you install any electrical aftermarket lately ? light, stereo..etc

 

Nope all of the electrical components have been on there for about a year or more. The only thing that I have changed is the light bar was hooked up to my switch pro with a relay instead of directly to the switch pro. I have sense put the light bar directly to one of the higher amperage switches on my switch pro.

 

someone here had issues with his switch pro and he had to get a new one under warranty.
how is the ground on your switch pro ?

 

@smslavin

 

Do you know if it caused issues with his interior lights?

 

not sure. he will reply shortly. I tagged him.
is the switch pro grounded correctly ?

 

I have it grounded to the negative battery terminal like it stated in the instructions. I also have my accessories wired to a terminal bar and common bus that is grounded to the chassis.

 

first, i did not get it replaced under warranty. i was way out of the date range. that being said, the switch pros folks were awesome whenever i spoke to them on the phone. everything checked out from a voltage and ohm perspective. it would run for awhile then shut off. a few minutes later it would reboot. no pattern. no other systems were affected. just the items connected to the SP.

this is key. make sure the SP is grounded directly on the battery neg terminal. do not ground to a frame or chassis point. also, has it gotten at all? is there any corrosion on the terminals? how did you connect your accessories to the SP? terminal block or butt splice?

 

do you have the SP app on your phone? if so, what’s the voltage reading for the SP?

 

Thats how I currently have it grounded is to the negative terminal of the battery. And I have them connected to a terminal block. I have checked all of the connections and they are tight and free of corrosion. The only accessory that does it is the light bar. And the interior dome lights.

 

I had the exact same problem (I have a switch pros, lights, winch, blah, blah) I thought it was a aftermarket wiring issue and it ended up being the battery. Start there. And get rid of that relay for the 40” bar, it shouldn’t be needed with the switch pro, I have my All my lights wired direct to it.

 

Yea I’ve ditched the relay for the switch pro. I had it on there because I originally hat it wired to a 3-way switch before I had the switch pro. I was thinking it was the battery looks or a north star 27F is in my future. Now just need to know if I want the elite or pro.

voltage reads around 13-13.5

 

that’s good. right where it should be. could be battery or alternator. truck stays running okay?

 

Truck runs fine. Headlights don’t dim or get brighter when the rpms fluctuate. Radio and all other lights are fine as far as I can tell. I don’t have any crazy amp draw. The only thing I can think of is just that the factory battery is starting to wear out with the cycling. My accessories currently are the light bar, two baja designs s2 reverse lights tied to switch pro triggered by reverse lights, an arb compressor that is tied to the switch pro through a relay and two kc cyclone lights under the hood again through the switch pro. I also have had baja designs fog lights for around two years no issues.

 

you don’t need to run the compressor through a relay. the SP is the relay and the higher amp switches on the SP will handle it.

 

I just got the switch pros adapter for the arb harness when I wired it up and that’s how it’s tied in. Essentially the arb switch got replaced by the switch pro. Worked out good for me because I could use the supplied harness from arb and keep everything clean. Also gives me the quick option to add solenoids if I ever wanna run lockers.

 

mine is the same setup. you threw me when you said it was going through a relay.

 

Has your 3-year bumper-to-bumper warranty expired?

 

The arb harness uses a relay that carries the load of the compressor when it’s on. That’s actually a good way to do it.

Yup I’m sitting at 44,xxx miles.

Yea I agree it’s weird that the head lights or non of the other lights flicker though. I went ahead and just ordered a battery since it’s coming up on 3 years old and it’s in getting colder here (WV) anyway. I went with the northstar pro 27F. My next step would be the bigger alternator from mechman that sdhq sells. Then I’m gonna have to find something to use up all that extra power hahaha.

 

Just an update the North Star battery is in and is a hoss. There was a little bit of corrosion on the bottom of my SDHQ terminals and the factory battery but very minimal. Cleaned them with sand paper before attaching them to the new battery. We will see if the issues continue but they haven't for the past two days. Im gonna take the old battery and get it tested to see if its okay or not. If it load tests okay I'll probably keep it on a maintiner to use around the house should I need a battery for something (tractors and boats). We've also got 3 tundras and a 4 runner in the family so should one of them need a battery it could probably work in a pinch. Thanks for all the help guys.