Fitting C-TEK connector, is it safe for electronics?

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noogieman

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Is it safe to screw a C-TEK battery charger connector onto the POS - NEG terminals inside the black box in the engine bay which is highlighted in the photo?
This box is used to jump start cars with dead battery.

I have fitted the same C-TEK connector to my bat in the trunk, depending how I park my car in the garage I would like to charge my bat either from the front or the rear.

Did anyone fit this connector in the engine room?
I don't want to fry any electronics so my Q is?
Is it safe to charge the battery from the engine bay?
 

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On my ML I only use the terminals under the hood for charging. The battery is well hidden under the passenger seat.
I use a CTEK as well.


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Charging under there is also the standard method on my car. I just use the crocodile clips, but permanent attachment is quite safe. Pretty well anything with stop/start will have a place like that to attach a charger. It’s so the BMS will see any current to the AGM battery.
 
Black box with POS/NEG terminals is considered as a convenient extension of the battery in trunk for jump starting dead cars?
Must be perfectly safe to connect the C-TEK eyelet connector to pos/neg terminals to charge battery from the engine.

It's very handy if you park your car in different directions in the garage having battery connectors in each end.
 
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On my W210 I connected the CKEK via the eyelets provided and ran an extension (CTEK) into the boot.
 
I expect the 210 pre-dates AGM batteries. It’s important to avoid connecting the charger to the battery terminals on those.
 
I expect the 210 pre-dates AGM batteries. It’s important to avoid connecting the charger to the battery terminals on those.
Why?
 
........................

It's very handy if you park your car in different directions in the garage having battery connectors in each end.

Wouldn't it be simpler to park the in the "right" direction when you want to charge the battery?
 
Wouldn't it be simpler to park the in the "right" direction when you want to charge the battery?

I'm not the only one in my garage.
Depending how the other tenants park their cars I need to have Eyelets in each end for easy access to power connection.
 
I'm sure some models of CTEK have an AGM mode?
 
I connected my eyelets direct to the main battery in the boot on my E55 and left it on for 24hrs.
Seemed OK when I discoonected the charger and started up.

Just need to find the best point inside the boot on a W212 now.
I assume with start stop which will be disabled there is a 2nd battery in the boot and the eyelets connect to the AGM main battery.
The MX5S does have the AGM function.
 
C-TEK charge 80% in 24 hours, the rest of 20% takes approx 10 days to fully load the battery, something to think about when you let your car sit for a long time over winter.
 
See #3 above
Ok not trying to be confrontational but would the bms see anything with the ignition off and all systems asleep? Genuinely curious as c-tek do suggest to connect direct to battery?
 
CTEK give that general suggestion. Many manufacturers say otherwise for their cars in the manual. The BMS certainly tracks power in and out. Some cars need coding in the car when the battery is being replaced, for the same reasons.
 
Took a photo today.
Mechanic told me it's all good charging battery from the engine bay although battery is located in the boot.
 

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Has anyone with a W212 fitted the fly lead in the engine bay?
I can see the + and - points but neither will accept the circular ring that is on the end of the Ctek lead?
 
The owners manual should specify a safe maximum charging voltage in terms of potential damage to the cars electronics. Mine states that the charger output must not exceed 14.8 volts. Some chargers with a desulphation mode may exceed the safe voltage in which case the battery should be disconnected before charging.
 
Has anyone with a W212 fitted the fly lead in the engine bay?
I can see the + and - points but neither will accept the circular ring that is on the end of the Ctek lead?

Go to Halfords and buy some connectors that will fit, and replace the C-Tek ones with them.
 

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