NV2500 Mod - Anti Theft Switch

[OpenRoad]

I wired in a switch under the dash that prevents the engine from being started.  Specifically prevents the ignition relay and fuel pump relay from being energized when the ignition key is turned.  My impetus for doing this was concerns of leaving my camping van at remote trailheads for periods of time and coming back to find it gone.  Not to say that it prevents it from being broken into but at least I can (hopefully) still drive back to civilization.  It would take thieves quite a bit of time to figure out why the van does not start.  I located my switch where it is easily accessible but hard to find if you don’t know where to look.  I have attached some pictures and markups of the wiring diagrams from the service manual for reference.  No special tools needed but if you have a crimping tool to make butt splices in the wire it makes the job much easier.  You will need to remove the lower left hand instrument panel (pages IP-18,19 in the NV service manual) and unmount the fuse block (2 screws) to have access to the back side of it.  The blue wire on connector M38 is the one you need to cut into to wire your switch.  Butt splice new wires to the two cut ends of the blue wire and route to wherever you are locating your new switch.

If you want to test this out without first cutting any wires then just pull fuse 12 (10A) in the fuse block located behind the pop out door located lower left of the steering wheel.  The on/off switch (SPDT) switch I installed is in series with this fuse so pulling the fuse does the same thing as opening the switch.  Fuse pulled, engine won’t start.  I guess I could have just pulled this fuse whenever I felt I needed to secure my van instead of installing the switch but over time the switch will be easier.  Make sure your switch is rated for at least 10 amps and use large enough wire gage ( I used 14 GA which is slightly overkill).

Note, my van is a 2500 HD S V6 High Roof.  I think that the wiring will be the same for other models but I cannot confirm that.  So for the disclaimer, DO THIS AT YOUR OWN RISK.  Even though it works on my van I take no responsibility for how it will work (or not) on yours.

Reference pages from NV service manual:

PG-25

PG-26

PG-29

PG-81

PCS-19

IP-18,19

[Local Apparent Friday]

Great info, thanks for this.