MBE 4000 DDEC VI Troubleshooting – Section 131.3 SPN 4226/FMI 3

Section 131.3
SPN 4226/FMI 3

This diagnosis is typically a circuit failed high.‪

Section 131.3.1
Open Circuit Check

Check as follows:‪

1. Check for multiple codes.
   1. If 3563/3, 51/4 and 4226/3 are present, repair the short to battery power between pin 117 of the 120–pin MCM connector, the Inlet Air Delta P Sensor and the Inlet Throttle Valve. See Figure "Inlet Air Delta P Sensor" . Refer to "131.3.1.1 Verify Repairs" .
      

      Figure 1. Inlet Air Delta P Sensor

   2. If 51/3 and 4226/3 are present, repair the short to battery power between pin 103 of the 120–pin MCM connector, the Inlet Air Delta P Sensor and the Inlet Throttle Valve. Refer to "131.3.1.1 Verify Repairs" .
   3. If only 4226/3 is present, go to step 2 .
2. Turn the ignition OFF.
3. Disconnect the Inlet Air Delta P Sensor.
4. Measure the voltage between pin 3 of the Inlet Air Delta P Sensor and ground.
   1. If the voltage is greater than 5 volts, repair the short to battery between pin 3 of the Inlet Air Delta P Sensor and pin 109 of the 120–pin MCM connector. Refer to "131.3.1.1 Verify Repairs" .
   2. If the voltage is less than five volts, replace the Inlet Air Delta P Sensor. Refer to "131.3.1.1 Verify Repairs" .

Section 131.3.1.1
Verify Repairs

Verify repairs as follows:‪

1. Turn ignition OFF.
2. Reconnect any electrical connections that were disconnected to perform the diagnosis.
3. Clear codes with DDDL 7.0 or latest version.
4. Start and bring engine up to operating temperature (over 140°F/60°C).
5. Verify operation is satisfactory and no warning lamps illuminate. If warning lamps illuminate, troubleshoot the codes. If assistance is required, call the Detroit Diesel Customer Support Center at 313–592–5800.