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Re: 2001 Mack MR-Series Electrical Power Issue
Posted to HD/Fleet Forum on 9/26/2013 10 Replies

I just checked the schematics and the power is deliver to the 70 amp power relay. Your VCU triggers the power relay on circuit VJ3-13 it goes to your 85 pin on your relay. When you engage the starter are you seeing voltage on VJ1-2 at the VCU? Login to read more.

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