12v to domitec fridge

vinniem

Hi all, help needed with this. I am not getting 12v to 3way fridge when engine running and 12v switch selected. Have checked all van fuses and seem ok. My cbe pc-100tr distribution board has a fuse for fridge which is ok but is there a relay or something on this unit or another component i should be looking at. Any help advice greatly apreciated.

niloc1951

vinniem wrote: »

Hi all, help needed with this. I am not getting 12v to 3way fridge when engine running and 12v switch selected. Have checked all van fuses and seem ok. My cbe pc-100tr distribution board has a fuse for fridge which is ok but is there a relay or something on this unit or another component i should be looking at. Any help advice greatly apreciated.

The cbe unit should have a connection where the feed from the engine battery arrives.
1 Check first if you have a voltage coming in there
If no voltage
Check for a break in the wire from the battery or a blown inline fuse.
If OK
2 Check if the output to the fridge is sending power
If no voltage
There is a fault within the cbe unit (if the fuse is ok)
If OK
Check for a fault between the cbe unit and the fridge
If no voltage
There is a fault between the cbe unit and the fridge
If OK
The fridge itself is faulty.

All the tests need to be done with the engine running, except the first test as the relays, which control the circuits to the fridge and habitation battery charging, close to make the circuits when the alternator starts producing charge are built in the the cbe unit (in mine are anyway)

Best of luck.

Aidan_M_M

what base vehicle is it?

vinniem

Thanks Niloc1951, will give it a go tomorrow evening. Any idea how to get front plate off fridge i.e where the selector switches are?

Aidan, its a Transit jumbo MK7 140ps RWD. Unusual problem only developed after winter, camper blow heater step buzzer and frige on batt all went together. Ignition switch alternator cct in common here but have checked that out. Batteries sending out 14.3v when engine running. Really confused here and need fridge running on batteries for upcoming road trip to France in early April. Any suggestions etc greatly appreciated. Thanks Vinnie

Aidan_M_M

who wired it? I know a good few lads don'tuse the Zig unit fuse for the fridge , instead fitting their own D+ switched relay and fuse in the engine bay to take the charge back to the red 12v switch . Them red switches burn out a lot too , as they take the full current through them that goes into the heating element.

vinniem

Aidan the coachbuilders wired it, checked fuses under bonnet and in cab area behind glovebox but have not checked relays as did not have an english transit manual (getting one today) Where is this 12v red switch you mentioned? Thanks

Aidan_M_M

ah its on the front of the fridge itself , but you prob have the newer one with a rotary knob . can you access the back of the fridge , or the top of it?

vinniem

Hi Aidan, my fridge has two rotary knobs on front. Managed to get this cover off this evening and could just abou access terminal strip with 12vDC into fridge. No voltage there with engine running so looks like back to CBE unit.. are these units easy to source? Thanks

Aidan_M_M

simple answer , no . I repaired a few , by finding the 12v in , the alternator signal , and the wire out to the fridge. And then fitting a standalone 70amp charging relay into it , Simple , cheap , and reliable .

Aidan_M_M

another thing , the CBE units , I've often seen the pins in the multiplugs to burn and deforem , not letting the current through .

Buford T Justice

Aidan_M_M wrote: »

simple answer , no . I repaired a few , by finding the 12v in , the alternator signal , and the wire out to the fridge. And then fitting a standalone 70amp charging relay into it , Simple , cheap , and reliable .

Usually on the inside/ middle of the terminals on the alternator, and its a light enough cable. Easy to spot, and if you hast a multimeter, sorted!

Aidan_M_M

I meant fitting a standalone relay inside the CBE unit , as the coach builts often run just the one wire back from the engine battery . You're getting pretty Hot at the aul autosparks , FMG!

Buford T Justice

Ta for that.

I've always been into electrics and have always had a hand in wiring....

Doing the camper van has taken it to a completely new level though.

vinniem

Hi lads, thanks for help. The wiring in my camper (Chausson) is absolutely terrible no such thing as organised looms or labeled cables/wires, rats nest/s really. Getting 14v into CBE with engine running and around 12V with engine off. Any idea which wire into CBE is from the alternator? Or which cable/wire from CBE is to fridge? Got no electrical drawings or anything like that. Thanks

Buford T Justice

vinniem wrote: »

Hi lads, thanks for help. The wiring in my camper (Chausson) is absolutely terrible no such thing as organised looms or labeled cables/wires, rats nest/s really. Getting 14v into CBE with engine running and around 12V with engine off. Any idea which wire into CBE is from the alternator? Or which cable/wire from CBE is to fridge? Got no electrical drawings or anything like that. Thanks

Technically, the cable won't be coming from the alternator. It'll be coming from the main battery circuit via a relay controlled by the alternator. I'm not familiar with the unit you have so can't help directly, but a toner or a multimeter and a bit of patience should see you right

Aidan_M_M

It'll be a smaller core cable , not a heavy red or black one . Often Yellow , green or blue .

It'll only be "live" with the engine running .