Need help troubleshooting CTek d250sa that's not charging, no lights come on

joelwatts

New member
I have installed this charger in my truck to charge an axially battery to power a fridge and lights. Everything is installed as the instruction call for, the only variation is that I installed a ground post connected to the chassis where I could connect all the other ground wires- fridge, lights, switch control box, CTek. I connected to the ignition by putting an ad-a-circuit to an ignition circuit in the fuse box. With the CTek disconnected, all the other wires measure 12. 5v or so. When the CTEk is connected, the voltage measured at the ignition connection is around 5v. The only time lights ever come on is for just a second when the axially battery is connected. Is my CTek faulty? Any help is greatly appreciated as I am trying to get this settled before Friday so I can escape to the mountains. Thanks.
 

john61ct

Adventurer
Has it ever worked, like testing on a bench?

Note it's fine to have your "chassis reference" (not really ground) tied into the negative return path of your various DC power circuits at multiple locations around the vehicle.

However with anything

important
expensive, or
high current

I personally do not rely on the vehicle chassis **as** the negative return, except say the starter / alternator / engine block arena.

Nice quality terminators & fittings, both pos & neg the same length and fat gauge boat cable, all properly crimped and tested. . .

Not saying the cause of your problem but as general FYI.
 

joelwatts

New member
Thanks john61ct. It seems like the ctek is not getting enough voltage to come on. Specs say it has to have something like 9. When everything is connected according to install directions , and I test voltage at the input from the starter battery, it’s only 5 or 6. I disconnected everything and tested that at 12.40v until I connect the negative from the ctek to the negative aux battery which is also grounded to chassis but that’s seems to be when it drops to 5 or 6 v
 

john61ct

Adventurer
Again, has the unit ever worked? Immediate goal is to remove all other possibilities and confirm the DCDC is not broken.

Try running a nice fat gauge +/- pair from your Starter battery terminals direct to the inputs of the DCDC.

Or set it up on a test bench with everything right next to each other.
 

john61ct

Adventurer
What is the max amps passed by the DCDC, and are the wires all sized accordingly, what AWG?

Test for voltage drop and resistance of each segment.

Are all the batteries involved in good shape?

Starter should be Fully charged, also consider running the engine so the alternator is outputting.

The target House battery should be healthy, as verified with a load test not just voltage, and at least 3/4 charged up.
 

joelwatts

New member
I don't know if the unit ever worked, this is the first time using it. Ok, what I know now (I just came in from the garage, so I'll have to check the other things tomorrow): House battery is brand new AGM, currently 11.84 v. Voltmeter at starter battery is 14 something v. I tested with ignition on (CTek is connected to ignition circuit) and with engine running for good measure. The wires are all sized according to the length of run as listed in the Ctek manual. The charger draws 20 amps from the starter. I should say that I am pretty much a novice at vehicle electrics, but I spent a lot of time planning this out before I started. All the lights on the charger come on for two seconds when I'd connect the ground, but then it would go off, however I did notice that the led indicator for current saving mode is on, but I think it should be charging the AGM since it is 11.84v
 

joelwatts

New member
I just saw a video where the guy switched to heavier gauge wire and that solved his voltage drop problem. Even though I am using the AWG specified in the manual, maybe I should change to and see what happens.
 
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john61ct

Adventurer
> House battery is brand new AGM, currently 11.84 v

That should be low enough. As stated, load test that batt.


I am unclear about some of your texts.


> All the lights on the charger come on for two seconds when I'd connect the ground, but then it would go off, however I did notice that the led indicator for current saving mode is on

Look at the manual for LED error codes.


> I connected to the ignition by putting an ad-a-circuit to an ignition circuit in the fuse box.

That is just for signaling not power, correct?

Also, be specific about your AWG vs length specs.


> With the CTek disconnected, all the other wires measure 12.5v or so

> When everything is connected according to install directions, and I test voltage at the input from the starter battery, it’s only 5 or 6.

Those two above conflict.

Measure at the Starter battery post, and compare to at the DCDC input. In all conditions - try with IGN off, IGN on but motor not running, and with motor running - the two points should be very very close to each other.

> The only time lights ever come on is for just a second when the axially battery is connected

Use House battery, "axially" is something else.

> until I connect the negative from the ctek to the negative aux battery which is also grounded to chassis but that’s seems to be when it drops to 5 or 6v

The House batt should always be connected to the DCDC. Check polarity of course.

Your IGN on signal is what turns the DCDC on/off.


> The charger draws 20 amps from the starter.

You mean from the alternator right? How do you know? That would mean it is working fine!
 

rayra

Expedition Leader
when you say "ignition circuit in the fuse box" what are you actually referring to? I don't think you should be using any small fused circuit as a power source for a battery charger. SHouldn't that charger be connected to your alternator output / charge wire / Starter (+)? Or if the CTEK itself doesn't do it, some form of high amp solenoid that is triggered by a keyed circuit, so the ctek can only draw juice when the alternator is putting out power.
/not familiar with the device or exactly how you are supposed to hooking it up, or how you are intending to hook it up. Got any links or wiring diagrams. Reading only 5V when that 'ignition circuit' is hot and probed is usually something crosswired, or you picked a circuit that's only passing that voltage in the first place, like for a USB port
 

calicamper

Expedition Leader
Many of these units are closed loop. You add a ground and they go into protect mode or fry. Get rid of the ground, neg to the battery. I bet it works fine after that. Most solar controllers are the same way.
 

john61ct

Adventurer
There does need to be a closed "loop" circuit both from (+) and back to (-) each battery, aka negative return, or current cannot flow.

The negative return of both circuits is **usually** in common with the chassis frame "ground" but that is not necessary, the output side negative could be isolated.
 

joelwatts

New member
John61ct, thanks for your help. I figured out the problem. The cable from battery to the charger was too small gauge, even though it was specified in the installation manual.
 

john61ct

Adventurer
Yes, maybe just sized for safety rather than reducing voltage drop

use Blue Sea's Circuit Wizard for wire sizing.

but quality properly crimped terminations / connections are also critical

learn how to use your DMM for checking for resistance issues.
 

joelwatts

New member
Okay, when I last posted I didn't see all the other replies for some reason, but I probably spoke too soon. I was hopeful because it worked after i decided to use jumper cables from the starter battery + to the charger input, and from the starter - to the house battery -, per wiring diagram (used jumpers to see if AWG was too small). It seemed to be working, the correct LED indicators came on for showing that it was charging the house battery. So i cleaned up all the tools and went to bed. The manual called for 10 AWG for 15' from starter battery to charger (20 amp draw), and the same from charger to ground. Today I got 6 AWG for those two runs (after seeing a youtube video where that solved the problem). It didn't work.
when you say "ignition circuit in the fuse box" what are you actually referring to? I don't think you should be using any small fused circuit as a power source for a battery charger. SHouldn't that charger be connected to your alternator output / charge wire / Starter (+)? Or if the CTEK itself doesn't do it, some form of high amp solenoid that is triggered by a keyed circuit, so the ctek can only draw juice when the alternator is putting out power.
/not familiar with the device or exactly how you are supposed to hooking it up, or how you are intending to hook it up. Got any links or wiring diagrams. Reading only 5V when that 'ignition circuit' is hot and probed is usually something crosswired, or you picked a circuit that's only passing that voltage in the first place, like for a USB port
The ignition circuit is just a signal to tell the charger that the vehicle is running so it only charges when it is running.
 

joelwatts

New member
> All the lights on the charger come on for two seconds when I'd connect the ground, but then it would go off, however I did notice that the led indicator for current saving mode is on

Look at the manual for LED error codes.

- yeah, there are error codes but doesn't cover what I saw.


> I connected to the ignition by putting an ad-a-circuit to an ignition circuit in the fuse box.

That is just for signaling not power, correct?

-yes

> The charger draws 20 amps from the starter.

You mean from the alternator right? How do you know? That would mean it is working fine!
[/QUOTE]

-- i meant its supposed to draw amps, when working, and yes, from the alternator
 
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