Fried board in climate control????

[stevebfl]

Well I was going to suggest just disconnecting the pump for the summer and I guess you already have.

The test of the pump would be to jump it from the battery with a fused jumper and an inductive ammeter on the wire. It should probably have less than 1000ma draw.

You are right that the MB service manual doesn't discuss this. The main reason for that is that this kind of testing is basic auto repair 101. Service manuals do not teach auto repair and electrical theory. Those of us who use them as intended would revolt over the wasted text. Service manuals are designed for use by experienced technicians, who don't have time for reading a bunch of basics. In the case of this issue MB should give an amp spec for the motor and they don't. They do not need to tell a technician how to test it.

My spec of 1000ma, 1 amp, is a guess it could be 2 or 3 amps. It would be nice to have that info.