Section 121.1 SPN 3659/FMI 6

Section 121.1
SPN 3659/FMI 6

This diagnosis is typically the Electronic Unit Pump Cylinder #1, Circuit Shorted to Battery.‪

Section 121.1.1
Circuit Shorted to Battery

Check as follows:‪

  1. Turn ignition OFF.
  2. Disconnect the MCM 120-pin connector.
  3. Using the J-48475 Breakout Box and J-48583 overlay, connect the MCM side of the harness ONLY.
  4. Turn ignition ON.
  5. Measure the voltage between pin 14 of the J-48475 Breakout box and ground.
    1. If voltage is greater than 0.5v, contact the Detroit Diesel Customer Support Center at 313–592–5800 for MCM replacement.
      Click to see this graphic in a separate window

      Figure 1. Electronic Unit Pump #1

    2. If voltage is present, repair short to power between pin 14 of the MCM 120-pin connector and the Electronic Unit Pump Cylinder #1. See Figure "Electronic Unit Pump #1" .


EPA07 MBE 4000 DDEC VI Troubleshooting Guide - 6SE568
Generated on 10-13-2008

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