MBE 900 DDEC VI Troubleshooting – Section 93.2 SPN 1636/FMI 3

Section 93.2
SPN 1636/FMI 3

The diagnostic condition is typically Intake Manifold Temperature Sensor Open Circuit. The following procedures will troubleshoot SPN 1636/3.‪

Section 93.2.1
Short to Power Check

Check as follows:‪

1. With the Intake Manifold Pressure/Temperature Sensor connected, check for multiple codes.
   1. If fault codes 1636/3 and 3563/3 are active, repair open circuit between pin 52 of the 120-pin MCM connector and pin 4 of the sensor. Refer to "93.2.1.1 Verify Repairs" .
   2. If only fault code 1636/3 is active, go to step 2 .
2. Disconnect the Intake Manifold Pressure/Temperature Sensor.
3. Disconnect the 120–pin MCM connector.
4. Measure the resistance between pins 3 and 4 of the Intake Manifold Pressure/Temperature Sensor harness connector.
   1. If the resistance is less than 5 Ω, repair the short between pins 52 and 106 of the 120–pin MCM connector. See Figure "Intake Manifold Pressure/Temp Sensor Wiring" . Refer to "93.2.1.1 Verify Repairs" .
   2. If the resistance is more than 5 Ω, repair the short to power on the circuit between pin 106 of the 120–pin MCM connector and pin 3 of the Intake Manifold Pressure/Temperature Sensor. See Figure "Intake Manifold Pressure/Temp Sensor Wiring" . Refer to "93.2.1.1 Verify Repairs" .

Figure 1. Intake Manifold Pressure/Temp Sensor Wiring

Section 93.2.1.1
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.