This method may save some wiring and some work.

1) Tap the antenna cable to get a 'switched' 12V. I think there is a wire in the cable bunch which is switched whether the radio is on or not. Run it thru a 20A relay to switch ...
2) Tap the trunk light for 'constant' 12V and wire it thru the relay.

Bingo. Now you have a switch 12V with a build-in fuse. It should have enough juice to drive the grease pump. This is an alternative anyway.

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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

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