On a Putzmeister MR 688 series the PTO Pump/Drive switch gets its power from a fuse located in the Mack fuse block. I regret to say I am not completely clear on the year ranges. But it is 1990 to 2006 or so.

It is located under the dog house in the main fuse block, some of them are Circuit Breakers and some are replaced with Mini fuses of the same amp range, Do you have a spare, Can you find it at 0 dark 30 with the mud backing up?

I have taken pics of the location to help me in the schools I thought you might want to check and locate your fuse before it gives you a problem; this fuse powers the Air shift valve and the coil on the 1K27 main power relay.


As always the Customer support group is there to help answer questions. Use the tool available to you. All Mfg’s are motivated to helping you keep your unit operating.

Alan Woods

I will also be available to help if you have specific Putz questions.

800 890-0269 is the Main contact # 24/7

woodsa@putzam is my e-mail

360 600-5695 Cell

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