Mice in my cab

Last week I noticed the paper towels under the back seat were a bit chewed up. Small pieces of tissue were scattered around under the back seat area. I did not see any nest area or smell any urine. I thought to myself "I can't imagine how critters would get inside the cab!" So I cleaned the tissue up and sprayed "Critter Ridder" under and around my truck.
Yesterday the tissue was bit up again, so I put sticky traps in the back of the cab. Sure enough, two mice were trapped in the sticky goo! Now I have to find the access hole or holes and maybe a nest somewhere.
Any helpful hints?
I do live in a rural area next to the water in Northern Michigan. Critter haven.

 

I'm not familiar enough with the 4th Gen to suggest where they're getting in, but I have a funny story about mice in the cab.

We had an elderly gentleman come in the shop complaining of mice in his cab. He said he would find "mouse manure" in his truck and they were stealing his candy. I looked and found a boot on the firewall with a slit in it where someone had run a wire in. I told him to watch under the dash and I'd stick my finger in the hole so he could see where it was from inside and he could seal it up with some tape. I stuck my finger in the boot and he screamed and started falling backwards across the parking lot, screaming and arms flailing. He finally stumbling down about 10 yards away. He said he thought my finger was a mouse and it had scared him! He would have crashed and possibly killed someone if he'd seen a mouse while he was driving.

 

I am sitting in the Dr's office reading this and I burst out laughing!! That is a funny story. Thanks for sharing!

 

Be thankful they're not pack rats! Just had one in my boat. What a mess.

 

I had a 2008 BMW Z4 two seat convertible. The winter before I built my pole barn, I stored it on the pole barn site which had all the gravel in place. I bought the best outside cover I find, and put it to bed for the winter. In the spring, I took off the cover and opened the door - reeked of mouse urine! I finally found the nest(s), the hvac unit and fan were full of nesting material. Apparently they climbed up through the hvac drain, which is a 1"x2" plastic tube on that car. It took me a month to tear the complete dash out so I could get the hvac unit out. Many of the plastic/rubber parts had been urine soaked so long I couldn't get the smell out of them. Ended up costing me over $800 to order new parts, many had to come from Germany. In the end, It went back together with no lingering smell. I put some stainless mesh over the end of the drain to keep any curious rodents out.

 

I am definitely going to investigate the access areas. Fortunately there is a lack of odor or poop! I am guessing the mice come in to get nesting material and build elsewhere.
I did have to replace the hood insulation this spring from due to rodents!
Time for a cat!!!

 

@Herman8r, They'll climb up the tires and then it's a highway under the truck for them! Check all wire access areas. Also check your HVAC drain tube area. They can fit through a 1/4" - 3/8" hole. Keep the grass and weeds cut back from where you park. I went to bait stations around where the truck is parked. So far so good! Good luck finding the hole!

 

@Topzide, funny thing is, the only area where I can find any evidence is under the back seat drivers side. I leave the seat section up against the back. Fold out floor section down. In the hidden hole under the seat back I store some TP paper and blue paper shop towels. There are untouched terrycloth towels in the back seat, a ripe apple up front, sweatshirts on the passenger seat. All untouched. The mice really like those blue towels! So far I have found 2 little poop pellets. And just a little bit of shredded paper towels. My guess is the mice grab the paper towels for a nest and exit the truck....at least my hopes anyways. I examined under the truck every place I could think of. No trace. Sneaky little S#$ts!!.
But I guess the blue paper towels are a lot better choice to use as bait so far. I put the towels back under the seat next to the sticky trap along with a camera pointed at the suspect location. Got to love that sticky trap!!

 

Air vents in back of cab?
Had mice get in there at a goat show in my 14.
It is behind the insulation board behind the back seat.
Good luck

 

Thanks Cissco. I had a glimpse of those while I was looking under the cab/truck bed area. Was hard to view that area. Did you take out the back seat? Looks like a pain to do so.

 

The newer body style may be different, but, the HVAC outside air intake is a big hole with no screen in the cowl. When the ignition is off the recurc door goes to the middle position bypassing the screen over the cabin air filter in my 2018. Mouse/critter highway as shown here:

https://www.turbodieselregister.com/threads/cowl-scuppers-missing-aka-plenum-drain-flap-plug.272676/

The highway for em is up the cowl drain in the fender (the wheel well black plastic is part of the drain critter highway) and through the fresh air intake for the HVAC. The flappers do not stop them. I use spearmint oil sprayed around the tires to keep the critters down. Also spray the area around the bottom of the fender with the door open as this is the bottom of the drain. (Good trash collector location there too.) NO FOOD of any kind left in the cab.

Vacuum the top of the cabin air filter screen before removing it as there may be a poo pile on top of it.

Also check/pull the hood liner insulation as they like to nest on top of that.

 

Thanks for the info @Tuesdak. They got into the hood liner last season. $250 */- to replace it. The battery insulation has been munched on also.
How do you access the top of the cabin filter?
I will check that next.
So far, no nests or urine smell in the cab.
I think @Cissco is correct with access area----vent behind the back seat. Looks like a project for next week. In the meantime, I am loaded Critter Ridder, Sticky Traps and bait traps.

No activity shown on the Nest Cam last night.

Happy 4th of July Everyone. Stay Safe.
HJR

 

in my 2018 it's pull the glovebox. Ignition off so the recurc door is out of the way and it's a plastic large hole screen on top of the cabin air filter box.