63.3
TROUBLESHOOTING FLASH CODE 63
63.3.5
Verify Installation of Starter Relay Harness Overlay Service Kit
Use the following procedure to verify installation of the starter relay harness overlay service
kit on Optimized Idle equipped vehicles only.
1. Turn ignition to ON position. Start engine.
2. Toggle cruise ON/OFF switch from OFF to ON. The Optimized Idle light should flash.
3. After the engine shuts down, turn the thermostat on by pressing any button.
4. Press UP or DOWN arrow until the heat or cool symbol begins to flash.
[a] If the engine starts, the repairs are complete. Refer to section 63.3.9.
[b] If the engine does not start, refer to section 63.3.6.
63.3.6
Engine Does Not Start in Optimized Idle Mode
Perform the following steps to start the engine.
1. Verify the hood is closed; the transmission is in neutral; the parking brake is set; and
the vehicle wheels are blocked.
To avoid personal injury, before starting and running the
engine, be sure that the vehicle is parked on a level surface
and that the wheels are properly blocked.
2. Remove the overlay relay from the relay block.
3. Measure voltage between terminal 85 and terminal 86 of the relay block.
[a] If voltage measurement is less than 4 VDC, the white wire in the overlay harness is
open. Repair the open circuit between the overlay harness and the hood/cab switch.
Refer to section 63.3.5.
[b] If voltage measurement is more than 4 VDC, the relay is inoperative. Replace the
relay. Refer to section 8.6.5 of the proper engine Service Manual. Verify the repairs.
Refer to section 63.3.9.
[c] If this is a Series 55 engine, refer to section 63.3.7.
63.3.7
Verify Harness
Perform the following steps to verify harness.
1. If this is a Series 55 engine, verify the engine harness is correct, especially PWM 3 and 4.
[a] If the harness is not correct, replace it. Refer to section 63.3.9.
All information subject to change without notice.
63-8
6SE497 9709 Copyright © 1997 DETROIT DIESEL CORPORATION
