This fault code indicates that there is a short to power.
Section 58.1.1 Short to Power Check
Check as follows:
Turn the ignition OFF.
Disconnect the fan control solenoid connector.
Turn the ignition ON (key On, engine OFF).
Measure the voltage between pin 1 of the fan control solenoid connector and ground.
If the voltage is greater than 11.5 volts, repair the short to power between pin 1 of the fan control solenoid connector and pin 98 of the 120–pin MCM connector. Refer to "58.1.1.1 Verify Repairs"
.
Reconnect any electrical connections that were disconnected to perform the diagnosis.
Clear codes with DDDL 7.0 or latest version.
Start and bring engine up to operating temperature (over 140°F/60°C).
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.
EPA07 Series 60 DDEC VI Troubleshooting Guide - 6SE567