Immobilized problems

Hello all,
We went up to check our van,  having lastbeen to it 5 weeks ago. Although we have left it for this length of time before, it has always started first time. Yesterday, no joy, despite panel telling us the vehicle battery had a good level of charge in it.
Went up to jump start it today. Still not starting and whilst trying to turn the engine over, the immobilser and door look activating without us touching the fobs. We assumed from this that a flat battery was not the problem.
Just wondered if anyone could shine a light on this or if a similar problem has been experienced.
Liz

So the engine turned over on the starter as willingly as normal, but it would not start? Were there any warning lights or other symbols displayed on the dash? I don't know your base vehicle at all, but in general if the immobiliser is not recognising a valid key, you should get an indication of that on the dash (on a VW you typically get a "Key?" message).

Is it fair to assume that it's diesel engined?

Hi Mojo,
It's a Peugot boxer. No engine did not turn over at all and we didn't notice any warning lights on dash.
Thanks,

Liz

The description is a bit vague, but you say that you attempted to jump start from a known good battery - if the engine won't turn over it's not likely to be an immobiliser problem. If you got no lights at all up on the dash with the ignition on then there are a number of possibilities, the most basic of which is a problem with the ignition switch.

Is it fair to assume that it's diesel engined?

Sorry, when I said no warning lights came up, I should have added that the usual dash lights that display on ignition did light up, just nothing untoward indicating a fault.
We jump started it from our car which has a good big battery and the motorhome is a diesel engine.
It's  a bit of mystery really.

If the dash lights stayed illuminated when the key was turned to the start position that pretty much eliminates battery problems (as you would expect on jump start). If no click when the key is turned it would suggest maybe a problem with ignition switch, while if there is a click from a relay somewhere the first likely candidate would be the starter motor, solenoid and power/earth cabling to it.

But of course remotely diagnosing a problem like that isn't easy. Have you had your recovery company attend yet?

Thanks mojo, 
Very useful advice. Think our recovery company will be first port of call tomorrow

Hello,
An update on the immobilser problem. It eventually turned out that the vehicle battery had come to the end of its life, after the display panel assured us that its charge level was good! Obviously not good enough to turn the engine e over.
The van now has a new battery in place so hopefully, all will be well.
Thank you for the help a d advice.

Liz