DD15 Troubleshooting – Section 91.1 SPN 1636/FMI 3

Section 91.1
SPN 1636/FMI 3

This diagnostic condition is typically intake manifold temperature circuit failed high.‪

Check as follows:‪

1. Check for multiple codes.
   1. If 1636/3 and 2630/3 are present, go to step 6 .
   2. If only 1636/3 is present, go to the next step.
2. Disconnect the Intake Manifold Temperature Sensor.
3. Turn the ignition ON (key On, engine OFF).
4. Measure the voltage between pins 1 and 2 of the Intake Manifold Temperature Sensor harness connector.
   1. If the voltage is between 2.8 and 3 volts, replace the Intake Manifold Temperature Sensor. Verify repairs.
   2. If the voltage is less than 2.8 volts, go to the next step.
5. Measure the voltage between pin 2 of the Intake Manifold Temperature Sensor and ground.
   1. If the voltage is between 2.8 and 3 volts, repair the wire between pin 1 of the Intake Manifold Temperature Sensor connector and pin 52 of the MCM 120–pin connector. Refer to "91.1.1 Verify Repairs" .
   2. If the voltage is less than 2.8 volts, repair the wire between pin 2 of the Intake Manifold Temperature Sensor connector and pin 106 of the MCM 120–pin connector. Refer to "91.1.1 Verify Repairs" .
6. Measure the voltage between pins 1 and 2 of the Intake Manifold Temperature Sensor harness connector.
   1. If the voltage is greater than 3 volts, repair the short to power on either pin 106 or 119 of the MCM 120–pin connector. Refer to "91.1.1 Verify Repairs" .
   2. If no voltage is present, repair the open between pin 52 of the MCM 120–pin connector and the Intake Manifold Temperature Sensor and the Intake Air Temperature Sensor. Refer to "91.1.1 Verify Repairs" .

Section 91.1.1
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.

   ENGINE EXHAUST ‪
   To avoid injury from inhaling engine exhaust, always operate the engine in a well-ventilated area. Engine exhaust is toxic.‪

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.