So was the fuse blown again? The K-40 relay is usually checked by replacing it with a known good one. However, the problem may be external to K-40. If a fuse is blowing, something is causing it.
[edit]
The following loads connect to circuit 87, which is powered by K40 and that 10 Amp fuse:
B2/5 Hot film MAF sensor
K40 Relay module (HFM-SFI, HFM-LP, ME-SFI, EDC, base function)
Y3/4 Modulator pressure switchover valve (AT/CC)
Y3/5 Upshift delay switchover valve (AT/CC)
Y31/1 EGR valve vacuum transducer
Y31/2 Pressure control flap vacuum transducer
One of these is drawing too much current and blowing the fuse.

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
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