Go ahead and post the correct info for the OP. There is no need to challenge me, it is uncalled for. I do not own any gas MBZ. I did say some old MBZ works on temperature, may be 1988 is oooold.

If it woks on temperature then put the sensor in a tub of boiling water and measure the resistance. Jump the wires with a resister of the same value. The principle is the same.

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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.