This diagnosis is typically EGR Delta P Sensor short to ground.
39.3.1
Short to Ground Check
Check as follows:
1. Disconnect the EGR Delta P Sensor.
2. Disconnect the 120–pin MCM connector.
3. Measure the resistance between pins 1 and 2 of the EGR Delta P Sensor.
[a] If the resistance is greater than 5Ω, go to step 4.
[b] If the resistance is less than 5Ω, repair the short between pins 103 and 117 of the
120–pin MCM connector. Refer to section 39.3.1.1.
4. Measure the resistance between pins 2 and 3 of the EGR Delta P Sensor.
[a] If the resistance is greater than 5Ω, go to step 5.
[b] If the resistance is less than 5Ω, repair the short between pins 103 and 109 of the
120–pin MCM connector. See Figure 39-2. Refer to section 39.3.1.1.
5. Measure the resistance between pin 1 of the EGR Delta P Sensor and ground.
[a] If the resistance is greater than 3Ω, go to step 6.
[b] If the resistance is less than 3Ω, repair the short circuit between pin 1 of the EGR
Delta P Sensor harness connector and ground. Refer to section 39.3.1.1.
6. Measure the resistance between pin 3 of the EGR Delta P Sensor and ground.
[a] If the resistance is greater than 3Ω, repeat steps 3 through 6. If the results are the
same, call the Detroit Diesel Customer Support Center (313–592–5800).
[b] If the resistance is less than 3Ω, repair the short circuit between pin 3 of the EGR
Delta P Sensor harness connector and ground. Refer to section 39.3.1.1.
39.3.1.1
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.
