12v Not Working

Dave1978

Dave1978

Free Member
Joined
Sep 22, 2019
Posts
13
Likes collected
0
Funster No
64,640
MH
Bailey Autograph 765
Exp
Since 2015
I have a Bailey Autograph 765 i am looking for some advice on the 12v system
I can't find whats wrong. On EHU everything works fine as soon as i unplug to go to 12v i have nothing its as if its been switched off. I have changed the battery and checked all the fuses on thr PDU
Does anyone have any ideas?
 
have you checked the battery fuse
 
Yes checked all fuses in the PDU unit with multimeter one in there says van battery tests ok. would there be any other fuses anywhere else
 
Batteries have had it

Subscribers  do not see these advertisements

 
You say the van battery is ok but is the hab battery ok
 
Hab battery is brand new vehicle battery is good
 
Can you access the 12V input on the distribution unit, if so check for supply, that might narrow it down.
Cheers
Ed
 
Would that be on the back of the PDU unit behind the wires?
 
test things in one direction.
Start at the battery, stab the posts. confirm 12.6v (ish)
Follow the positive cable and test it at the next point you can get at it, if that's the PDU then test the input first, then look at the wiring diagram for that unit and test the output if you don't know which it is. Keep going until you find somewhere where 12.6v goes in and nothing comes out of where it should... There's your problem.

Subscribers  do not see these advertisements

 
Logic says there is a fault/break in circuit from battery to 12v system.... Perhaps!
Friend of mine ran caravan electrics, lights etc straight from EHU.. no leisure battery installed...
But obv. No EHU... No power ...
 
If you can post a picture of connections to the distribution unit, we may be able help further.
Cheers
Ed
 
Does this happen when you switch on the engine? If so it is a "design feature" of many UK motorhomes that the habitation 12v does not work when the engine is running.
 
No happens when i unplug the ehu i have checked all connections but can't find any issues with the wieing?
 
You day you have check the fuses in the distribution unit but what about the main battery fuse, normally next to the battery.

Subscribers  do not see these advertisements

 
Where is it i cannot see a main battery fuse do you know where it would be i cannot see an inline fuse on the lead
 
Just backing up a minute...
When you unplug the van to go to 12v things don't work....
What exactly doesn't work.
What socket stops working when you disconnect 240v.
 
Nothing works when not hooked up control panel has no display
 
As said already i think, this proves the link between the PDU and all the electrics including display panel are fine,
What it also suggests is the battery charger is in operation as this is probably what is supplying all your 12 ancillaries and display.
So by deduction that only leaves positive and negative cables from battery to PDU at fault.
Could be a crusty earth cable or a blown fuse on the positive.
You need to get in there as I said, with the multimeter in hand and probe from the battery to the PDU, somewhere along this chain is a break. Start with one lead clipped to hab battery negative post and probe various points on the positive back to the PDU, if you get to the 12v input of the PDU and have voltage there, positive cable is GOOD.
Remove earth clip from battery negative.
Place earth clip on PDU negative input... if you have 12v between positive and negative on PDU then both positive and negative cables are good then that leaves only the internals of PDU being at fault between pdu input and pdu output. We already know pdu output is good as it works on 240v fine.
It's not a complex system if you work through things in a logical way.
 
Last edited:
Sometimes it's the obvious that's missed. Have you tried switching the control panel on? Ours switches off when the engine is started and needs manually switching back on when engine stopped.

Subscribers  do not see these advertisements

 
Dave1978 said:
Would that be on the back of the PDU unit behind the wires?
Click to expand...
oh and get the PDU manual out or if you don't have it, search google for it.
As they say RTFM ?.
Confirm which plug is 12v input and test it with the multimeter!
 
Thanks handyandy i will check steve freeman i thought the panel went on automatically do you press the master switch to turn on?
 
Lenny HB said:
Normally right next to the battery my van has a 50 amp maxi blade fuse.
Click to expand...
I cant see it usually inline isn't it

Subscribers  do not see these advertisements

 
As said ours is a maxi blade fuse I don't know what Bailey fit but it must be fused.
 
Lenny HB said:
As said ours is a maxi blade fuse I don't know what Bailey fit but it must be fused.
Click to expand...
Would be easy if inline maxi fuse the swift was inline this bailey is my new van manual is terrible and i cannot see a fuse i will take another look
 
Dave1978 said:
I have a Bailey Autograph 765 i am looking for some advice on the 12v system
I can't find whats wrong. On EHU everything works fine as soon as i unplug to go to 12v i have nothing its as if its been switched off. I have changed the battery and checked all the fuses on thr PDU
Does anyone have any ideas?
Click to expand...
HI Dave
I have just got exactly the same problem on my 765. Did you resolve yours?
 
RCudmore said:
HI Dave
I have just got exactly the same problem on my 765. Did you resolve yours?
Click to expand...
I had the same problem it turned out to be a fault 20 amp yellow fuse in the rear fuse box under the seat says batt line. It’s worth a try changing it. Hope this helps you
 
RCudmore said:
HI Dave
I have just got exactly the same problem on my 765. Did you resolve yours?
Click to expand...
'Dave' has not visited the forum since 2019..

Subscribers  do not see these advertisements

 

Join us or log in to post a reply.

To join in you must be a member of MotorhomeFun

Join MotorhomeFun

Join us, it quick and easy!

Join us

Log in

Already a member? Log in here.

Latest journal entries

Back
Top