DD15 Troubleshooting – Section 31.4 SPN 164/FMI 3

Section 31.4
SPN 164/FMI 3

PN 164/FMI 3 indicates the Rail Pressure Governor Sensor circuit failed high (open circuit).‪

Check as follows:‪

1. Check for multiple codes.
   1. If faults for the Intake Manifold Pressure/Temperature Sensor are active at the same time, repair the circuit between pin 58 or pin 102 of the MCM 120-pin Connector and pin 2 or pin 4 of the Intake Manifold Pressure/Temperature Sensor. Refer to "31.4.1 Verify Repairs" .
   2. If only fault 164/3 is active, go to the next step.
2. Disconnect the Rail Pressure Governor Sensor connector.
3. Measure the resistance across pins 1 and 2 of the Rail Pressure Governor Sensor.
   1. If the resistance is greater than 4.7 k Ω, replace Rail Pressure Governor Sensor.
   2. If the resistance is less than 4.7 k Ω, go to the next step.
4. Turn the ignition ON (key ON, engine OFF).
5. Measure the voltage between pins 1 and 3 of the Rail Pressure Governor Sensor harness connector.
   1. If the voltage is between 2.75 and 3.25 volts, go to step 7 .
   2. If the voltage is less than 2.75 volts, go to the next step.
6. Measure the voltage between pin 3 of the Rail Pressure Governor Sensor harness connector and ground.
   1. If the voltage is between 2.75 and 3.25 volts, repair the open circuit between pin 1 of the Rail Pressure Governor Sensor harness connector and pin 102 of the 120-pin MCM connector. Refer to "31.4.1 Verify Repairs" .
   2. If the voltage is less than 2.75 volts, repair the open circuit between pin 3 of the Rail Pressure Governor Sensor harness connector and pin 58 of the MCM 120-pin connector. Refer to "31.4.1 Verify Repairs" .
7. Disconnect the 120-pin MCM connector and measure the resistance between pin 78 of the MCM 120–pin connector and pin 2 of the Rail Pressure Governor Sensor harness connector.
   1. If the resistance is less than 5 Ω, repair the short between pin 2 of the Rail Pressure Governor Sensor harness connector and pin 78 of the MCM 120-pin connector. Refer to "31.4.1 Verify Repairs" .
   2. If the resistance is greater than 5 Ω, replace the sensor. Refer to "31.4.1 Verify Repairs" .

Section 31.4.1
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.