Clearing Diagnostic Trouble Codes

1. Turn ignition switch to the ``OFF'' position.
2. Remove ECU power fuse as follows:
a. On C/K and R/V trucks, remove Stop/Hazard fuse.
b. On Astro & Safari vans, remove Horn/Dome fuse.
c. On G vans, remove Tail LPS fuse.
d. On S/T trucks, remove ECM B fuse.
3. Ensure ignition is in the ``OFF'' position, permanent damage to the ECU could be caused by removing power fuse with ignition in the ``ON'' position.