Trickle Charger not detecting battery unless removed...?

[Tokaido]

Hi there friends. I'm from the other side of the pond, but saw a lot of posts here mentioning the CTEK trickle chargers, so I hope to maybe find my answer here.

Car: 2023 Corolla Hybrid SE

Charger: CTEK MXS 5.0

Issue: I tried the eyelet pigtails first as I would love to have a easy access to charging the Battery without popping the bonnet. CTEK would not detect the Battery from a good ground spot, nor on the Battery cathode directly. Tried the alligator clamps instead. Same thing. I ended up seeing if pulling the entire battery out and using the alligator clamps that way would work, and it did. Very very odd... While it'll work for this time around, it is not suitable practice for me every week. Pics below.

Why is it reading when the battery is in the vehicle? There's certainly no relays or anything between where I had attempted to connect whilst in the vehicle. The alligator clamps should've worked, but to no avail... Has anyone else had success running the eyelet connectors? I really want to purchase the longer eyelet connector with the battery readout and run it to the tow hook cover, but I can't even get a proper connection in the vehicle.

Any help would be greatly appreciated!

Below, two circles of where I had initially tried to connect the ground eyelets. First the left, then the right. No dice. 

 

Below, depicts where I had connected the positive eyelet. You can see where I connected the negative eyelet as well, no success.

 

Below depicts ultimately what worked...

 

After just several minutes, the battery had read to Step 4, "Ready to go"... But I was out of time to try and plop the battery in. Will let it go further in steps just to ensure it's good.

[camellia30]

Well the manual says you're supposed to disconnect the Battery, but i'd still expect it to work in-situ.

Where were you going to run the cable after connecting the eyelets (so you don't have to pop the bonnet)?

 

[Tokaido]

On 5/5/2023 at 9:19 AM, camellia30 said:

Well the manual says you're supposed to disconnect the battery, but i'd still expect it to work in-situ.

Where were you going to run the cable after connecting the eyelets (so you don't have to pop the bonnet)?

 

The Battery was over dead, which is why it wouldn't sense the Battery and I had to remove it. So the problem has been solved.

To answer your question, the tow hook cover.

[Roy124]

Ray, good to know.  I had my Corolla hard wired as you tried and it worked with a flat Battery but only flat to would not start the system.  Pressing the Start button got lots of flashing lights. 

At this point the measured voltage was around 8v.  A couple of instance of flat Battery and that Battery was clearly damaged. 

You may have recovered your battery from a much worse condition but may well have cell damage. 

Check the voltage decay over time.  It should not be significant over a couple of days.  Get it checked out when you can