SPN 599/FMI 4
This diagnosis is typically both Cruise Control switches, SET and RES, are shorted to ground.
Check as follows:
- Turn the ignition ON (key ON, engine OFF) and place the Cruise Control Switch in the OFF position. DO NOT start the engine.
- Check the driver console display.
- If Cruise Control switch status RES is displayed, go to step 3 .
- If Cruise Control switch status SET is displayed, go to step 4 .
- Unplug the RES Cruise Control Switch.
- If RES status is no longer displayed, replace the Cruise Control RES Switch. Refer to “46.1.1 Verify Repairs” .
- If RES status is still displayed, repair the short to ground in the wire from the RES switch to pin 16 of the CPC #1 connector. Refer to “46.1.1 Verify Repairs” .
- Unplug the SET Cruise Control Switch.
- If SET status is no longer displayed, replace the Cruise Control SET Switch. Refer to “46.1.1 Verify Repairs” .
- If SET status is still displayed, repair the short to ground in the wire from the SET switch to pin 12 of the CPC #1 connector. Refer to “46.1.1 Verify Repairs” .
Verify Repairs
Verify repairs as follows:
- Turn ignition OFF.
- 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.