I’ve put my cool box into my unit today as start new job tomorrow so I’ve been in to get the can clean and put my stuff in, plugged the Coolbox in and it’s going for about 15 seconds then off for the same I only bought it in December. It’s been in my garage for 10 weeks and hardly been used so can’t understand why, not great timing but hoping there’s a simple fix?
It’s a man unit 63 plate, got a 12v mini socket which I have a plug for somewhere at home but I can’t see why using the 12v socket on the ash tray bit wouldn’t work, unless that’s a 24v socket but I don’t know?
The modern CANbus electrics on some vehicles can cause strange results when plugging stuff into the 12V or faglighter sockets. You might find it behaves normally with the ignition switched on. Easiest way to see if it’s a problem with the coolbox would be to try it in a different vehicle (e.g. your car) and see if it still misbehaves.
12v socket on MAN is done by current dropper and I bet the units batteries are not tip top so voltage is dropping below min fresh hold so dropper cuts out to protect start charge 
I tried with ignition on and engine running, I also tried in my car but the ■■■ socket in my car isn’t working unknown to me 
I’m hoping it must be a 24v socket and was turning itself off due to over power and when I plug it into the proper 12v socket it’ll go. The place is closed today and I don’t know anyone there to ask. It’s a nightmare starting the week without a fridge when I’ll be out all week.
blue estate:
12v socket on MAN is done by current dropper and I bet the units batteries are not tip top so voltage is dropping below min fresh hold so dropper cuts out to protect start charge
So does that mean it’ll just switch to constant once I’m up and running tomorrow?
OllieNotts:
blue estate:
12v socket on MAN is done by current dropper and I bet the units batteries are not tip top so voltage is dropping below min fresh hold so dropper cuts out to protect start chargeSo does that mean it’ll just switch to constant once I’m up and running tomorrow?
yes should do if not your cool box is ■■■■■■
What you describe screams 24v to me so that would be the first thing id check.
OllieNotts:
I tried with ignition on and engine running, I also tried in my car but the ■■■ socket in my car isn’t working unknown to me
I’m hoping it must be a 24v socket and was turning itself off due to over power and when I plug it into the proper 12v socket it’ll go. The place is closed today and I don’t know anyone there to ask. It’s a nightmare starting the week without a fridge when I’ll be out all week.
24into 12 goes pop 
So if it was that and if it’s (the box) is fused that ain’t the problem as the fuse should go first
I would go for check the wiring etc make sure you have a reliable power source and try again.
I took mine apart and ran the vacuum through it to clear dust etc from it and a drop of graphite grease on the fan etc helps keeping things running smoothly .
nick2008:
OllieNotts:
I tried with ignition on and engine running, I also tried in my car but the ■■■ socket in my car isn’t working unknown to me
I’m hoping it must be a 24v socket and was turning itself off due to over power and when I plug it into the proper 12v socket it’ll go. The place is closed today and I don’t know anyone there to ask. It’s a nightmare starting the week without a fridge when I’ll be out all week.24into 12 goes pop
So if it was that and if it’s (the box) is fused that ain’t the problem as the fuse should go first
Yep I managed to kill my last coolbox that way 
OllieNotts:
I’ve put my cool box into my unit today as start new job tomorrow so I’ve been in to get the can clean and put my stuff in, plugged the Coolbox in and it’s going for about 15 seconds then off for the same I only bought it in December. It’s been in my garage for 10 weeks and hardly been used so can’t understand why, not great timing but hoping there’s a simple fix?
It’s a man unit 63 plate, got a 12v mini socket which I have a plug for somewhere at home but I can’t see why using the 12v socket on the ash tray bit wouldn’t work, unless that’s a 24v socket but I don’t know?
That plug in the ash tray is 24v… What unit is it? 12v on the TGX I have is a hella style plug in the passenger footwell
I don’t know on model but it’s as big as most space cabs 2 bunks and that with the 2 hells sockets in passenger footwell I’ll dig the plug out tonight thanks for all your help 
the 12v socket will be running thru a mini dropper fitted by manafacturer and prob not big enough for cool box .
stevejones:
the 12v socket will be running thru a mini dropper fitted by manafacturer and prob not big enough for cool box .
Gets my vote. Dropper gets too hot, shuts itself off. Cools down, runs again for a bit until it gets too hot, rinse and repeat.
The ones I had a quick look at draw around 6A for the small ones, the 12V socket on the MAN is only rated at 5A off the top of my head.
the 12 volt mini (below) socket will power the cool box no problem, you seem to have plugged it into 24 volt cig socket.hopefully just popped the fuse
OllieNotts:
I don’t know on model but it’s as big as most space cabs 2 bunks and that with the 2 hells sockets in passenger footwell I’ll dig the plug out tonight thanks for all your help
Assuming your unit still has the covers in place on the hella sockets, the 12v one should be the white one but they are marked anyway. One 12v, one 24v
are you sure its a 12 volt socket ?- you might think it is but who knows who has been fiddiling with it . Get it checked with a voltage meter to make sure its 12 volt . To me it sounds like its 24 volt and your coolbox is cutting out (if your lucky it has a voltage overprotection circuit )
If its an MAN and its in the ashtray its 24v
Mines a weaco and is plugged into the hella 12v for a week at a time with no bother at all