The current draw of the auxiliary water pump is .25 amp both direct from battery or from the controller. However, the ground wire from the controler has no circuit and it had to be supplied.

Even unpluged the controller continues to shut down the fan about every 30 seconds for a second.

What is your best guess, as the next step?

This is from the 1987 model year info...sounds like the feedback pot is the problem....

Attached Files

87 W201 fixed mode.pdf (61.1 KB, 216 views)

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