There are fresh air vents that are open to invasion near the top and sides of the plastic-screened vent at the top of the radiator. You can see them on either side once you remove the upper plastic grill. I put plastic window screen material across the entire area up there by removing that plastic cover (held on by some screws) placing a piece of plastic screen across that opening, putting the plastic cover back on, then using RTV (gray) to glue the screen across the wedge-shaped side openings.
So far, so good.
The mice use the tires,then coolant lines and suspension parts, wires to crawl up into that space. You may also find that they like making nests up in the engine compartment. My guess is that coating that fairly heavily with engine cleaner, and not rinsing it off, might make that area less homey.

Bob

Sent from my iPad

On Sep 30, 2013, at 9:01 PM, Larry Alofs <lalofs@GMAIL.COM> wrote:

> Drier sheets, smelly ones like Bounce, in heater/ defroster openings,
> battery compartments, under back seat, near each door and hatch.
> 
> Larry A.
> 
> 
> 
> On Mon, Sep 30, 2013 at 9:34 PM, Alain Thibault <alainthibault@telus.net>wrote:
> 
>> I am going to store my camper in a garage where mice are present. I've
>> heard before that they can easily get in the van,  so I wonder If there are
>> any ways to prevent it. Thanks
>> Alain
>> VancouverBC
>> Westfalia 1986
>> 
>> Sent from my iPad 2