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

Tom

I did have 1 relay with some burn marks, I did switch out all 4 with known goods, no change.

Based on the schematic none of these relays should not turn on until the VECU sends power out on VJ3-13 and when there is power on VJ3-13 it is fine, it seems ... Login to read more.