I park 3 of my Mbz outside, 2 in the garage. I live in a rural area and I have rodents visit the cars at night.

I build a prototype with flashing high intensity LED light strip and put it under the hood. It seems to be very effective to keep the rodents away. It has a timer, a 5W solar panel and is attached to the battery. It is turned on at night and recharged during the day. It is kind of a trickle charger and rodents repellent device combined. So no issues if you leave the car out for weeks on end. Final costs will be $40-50. I am going to make 3 myself but I am wondering anyone here interested into getting one? It is not going to make me rich but would be a fun project. PM me if you want or comment here.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.