The typical diagnosis for this fault is an Intake Manifold Pressure Sensor short circuit.
111.3.1 Short Circuit Check
Check as follows:
1. Disconnect the Intake Manifold Pressure Sensor (IMP Sensor).
2. Disconnect the 120–pin MCM connector.
3. Measure the resistance between pin 2 and 3 of the IMP Sensor connector. See Figure 111-1.
[a] If the resistance is less than 5 Ω, repair the short between pins 87 and 102 of the
120–pin MCM connector.Refer to section 111.3.1.1.
[b] If the resistance is greater than 5 Ω, repair the short to power on pin 87 of the 120–pin
MCM connector. Refer to section 111.3.1.1.
111.3.1.1 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.
